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Home > Household Chemical Encyclopedia > Polychlorinated Biphenyls (PCBs) Polychlorinated Biphenyls (PCBs) Public Health, Toxicology, and PCB MSDS Information
Here where I live in Upstate South Carolina, huge Lake Hartwell is heavily contaminated with PCB, Mercury, and god knows what else to the point that eating any fish out of it is very unwise. Thanks a lot Sangamo Corporation and coal-fired power plants. If you would like to find out if your local bodies of water are also contaminated with carcinogenic PCBs, try my PCB Search Box below. The Environmental Protection Agency (EPA) identifies the most serious hazardous waste sites in the nation. These sites make up the National Priorities List (NPL) and are the sites targeted for long-term federal cleanup activities. PCBs have been found in at least 500 of the 1,598 current or former NPL sites. However, the total number of NPL sites evaluated for PCBs is not known. As more sites are evaluated, the sites at which PCBs are found may increase. This information is important because exposure to PCBs may harm you and because these sites may be sources of exposure. When a substance is released from a large area, such as an industrial plant, or from a container, such as a drum or bottle, it enters the environment. This release does not always lead to exposure. You are exposed to a substance only when you come in contact with it. You may be exposed by breathing, eating, or drinking the substance, or by skin contact. If you are exposed to PCBs, many factors determine whether you'll be harmed. These factors include the dose (how much), the duration (how long), and how you come in contact with them. You must also consider the other chemicals you're exposed to and your age, sex, diet, family traits, lifestyle, and state of health. Questions and Answers About Polychlorinated Biphenyls (PCBs):
What are polychlorinated biphenyls (PCBs)?PCBs are a group of synthetic organic chemicals that can cause a number of different harmful effects. There are no known natural sources of PCBs in the environment. PCBs are either oily liquids or solids and are colorless to light yellow. Some PCBs are volatile and may exist as a vapor in air. They have no known smell or taste. PCBs enter the environment as mixtures containing a variety of individual chlorinated biphenyl components, known as congeners, as well as impurities.
back to top What happens to polychlorinated biphenyls (PCBs) when they enter the environment?Before 1977, PCBs entered the air, water, and soil during their manufacture and use in the United States. Wastes that contained PCBs were generated at that time, and these wastes were often placed in landfills. PCBs also entered the environment from accidental spills and leaks during the transport of the chemicals, or from leaks or fires in transformers, capacitors, or other products containing PCBs. Today, PCBs can still be released into the environment from poorly maintained hazardous waste sites that contain PCBs; illegal or improper dumping of PCB wastes, such as old transformer fluids; leaks or releases from electrical transformers containing PCBs; and disposal of PCB-containing consumer products into municipal or other landfills not designed to handle hazardous waste. PCBs may be released into the environment by the burning of some wastes in municipal and industrial incinerators. Once in the environment, PCBs do not readily break down and therefore may remain for very long periods of time. They can easily cycle between air, water, and soil. For example, PCBs can enter the air by evaporation from both soil and water. In air, PCBs can be carried long distances and have been found in snow and sea water in areas far away from where they were released into the environment, such as in the arctic. As a consequence, PCBs are found all over the world. In general, the lighter the type of PCBs, the further they may be transported from the source of contamination. PCBs are present as solid particles or as a vapor in the atmosphere. They will eventually return to land and water by settling as dust or in rain and snow. In water, PCBs may be transported by currents, attach to bottom sediment or particles in the water, and evaporate into air. Heavy kinds of PCBs are more likely to settle into sediments while lighter PCBs are more likely to evaporate to air. Sediments that contain PCBs can also release the PCBs into the surrounding water. PCBs stick strongly to soil and will not usually be carried deep into the soil with rainwater. They do not readily break down in soil and may stay in the soil for months or years; generally, the more chlorine atoms that the PCBs contain, the more slowly they break down. Evaporation appears to be an important way by which the lighter PCBs leave soil. As a gas, PCBs can accumulate in the leaves and above-ground parts of plants and food crops. PCBs are taken up into the bodies of small organisms and fish in water. They are also taken up by other animals that eat these aquatic animals as food. PCBs especially accumulate in fish and marine mammals (such as seals and whales) reaching levels that may be many thousands of times higher than in water. PCB levels are highest in animals high up in the food chain. You can find more information about what happens to PCBs in the environment such as via aerobic and anaerobic degradation of polychlorinated biphenyls below. back to topHow might I be exposed to polychlorinated biphenyls (PCBs)?Although PCBs are no longer made in the United States, people can still be exposed to them. Many older transformers and capacitors may still contain PCBs, and this equipment can be used for 30 years or more. Old fluorescent lighting fixtures and old electrical devices and appliances, such as television sets and refrigerators, therefore may contain PCBs if they were made before PCB use was stopped. When these electric devices get hot during operation, small amounts of PCBs may get into the air and raise the level of PCBs in indoor air. Because devices that contain PCBs can leak with age, they could also be a source of skin exposure to PCBs. Small amounts of PCBs can be found in almost all outdoor and indoor air, soil, sediments, surface water, and animals. However, PCB levels have generally decreased since PCB production stopped in 1977. People are exposed to PCBs primarily from contaminated food and breathing contaminated air. The major dietary sources of PCBs are fish (especially sportfish that were caught in contaminated lakes or rivers), meat, and dairy products. Between 1978 and 1991, the estimated daily intake of PCBs in adults from dietary sources declined from about 1.9 nanograms (a nanogram is a billionth part of a gram) to less than 0.7 nanograms. PCB levels in sportfish are still high enough so that eating PCB-contaminated fish may be an important source of exposure for some people. Recent studies on fish indicate maximum concentrations of PCBs are a few parts of PCBs in a million parts (ppm) of fish, with higher levels found in bottom-feeders such as carp. Meat and dairy products are other important sources of PCBs in food, with PCB levels in meat and dairy products usually ranging from less than 1 part in a billion parts (ppb) of food to a few ppb. Concentrations of PCBs in subsurface soil at a Superfund site have been as high as 750 ppm. People who live near hazardous waste sites may be exposed to PCBs by consuming PCB-contaminated sportfish and game animals, by breathing PCBs in air, or by drinking PCB-contaminated well water. Adults and children may come into contact with PCBs when swimming in contaminated water and by accidentally swallowing water during swimming. However, both of these exposures are far less serious than exposures from ingesting PCB-contaminated food (particularly sportfish and wildlife) or from breathing PCB-contaminated air. Workplace exposure to PCBs can occur during repair and maintenance of PCB transformers; accidents, fires, or spills involving PCB transformers and older computers and instruments; and disposal of PCB materials. In addition to older electrical instruments and fluorescent lights that contain PCB-filled capacitors, caulking materials, elastic sealants, and heat insulation have also been known to contain PCBs. Contact with PCBs at hazardous waste sites can happen when workers breathe air and touch soil containing PCBs. Exposure in the contaminated workplace occurs mostly by breathing air containing PCBs and by touching substances that contain PCBs. You can find more information about exposure to PCBs in Chapter 6 of the toxicological profile. back to topHow can polychlorinated biphenyls (PCBs) enter and leave my body?If you breathe air that contains PCBs, they can enter your body through your lungs and pass into the bloodstream. We do not know how fast or how much of the PCBs that are breathed will pass into the blood. A common way for PCBs to enter your body is by eating meat or fish products or other foods that contain PCBs. Exposure from drinking water is less than from food. It is also possible that PCBs can enter your body by breathing indoor air or by skin contact in buildings that have the kinds of old electrical devices that contain and can leak PCBs. For people living near waste sites or processing or storage facilities, and for people who work with or around PCBs, the most likely ways that PCBs will enter their bodies are from skin contact with contaminated soil and from breathing PCB vapors. Once PCBs are in your body, some may be changed by your body into other related chemicals called metabolites. Some metabolites of PCBs may have the potential to be as harmful as some unchanged PCBs. Some of the metabolites may leave your body in the feces in a few days, but others may remain in your body fat for months. Unchanged PCBs may also remain in your body and be stored for years mainly in the fat and liver, but smaller amounts can be found in other organs as well. PCBs collect in milk fat and can enter the bodies of infants through breast-feeding. For more information on how PCBs can enter and leave your body, see Chapter 3 of the toxicological profile. back to topHow can polychlorinated biphenyls (PCBs) affect my health?Many studies have looked at how PCBs can affect human health. Some of these studies investigated people exposed in the workplace, and others have examined members of the general population. Skin conditions, such as acne and rashes, may occur in people exposed to high levels of PCBs. These effects on the skin are well documented, but are not likely to result from exposures in the general population. Most of the human studies have many shortcomings, which make it difficult for scientists to establish a clear association between PCB exposure levels and health effects. Some studies in workers suggest that exposure to PCBs may also cause irritation of the nose and lungs, gastrointestinal discomfort, changes in the blood and liver, and depression and fatigue. Workplace concentrations of PCBs, such as those in areas where PCB transformers are repaired and maintained, are higher than levels in other places, such as air in buildings that have electrical devices containing PCBs or in outdoor air, including air at hazardous waste sites. Most of the studies of health effects of PCBs in the general population examined children of mothers who were exposed to PCBs. The possible health effects of PCBs in children are discussed in Section 1.6. To protect the public from the harmful effects of toxic chemicals and to find ways to treat people who have been harmed, scientists use many tests. One way to see if a chemical will hurt people is to learn how the chemical is absorbed, used, and released by the body; for some chemicals, animal testing may be necessary. Animal testing may also be used to identify health effects such as cancer or birth defects. Without laboratory animals, scientists would lose a basic method to get information needed to make wise decisions to protect public health. Scientists have the responsibility to treat research animals with care and compassion. Laws today protect the welfare of research animals, and scientists must comply with strict animal care guidelines. Rats that ate food containing large amounts of PCBs for short periods of time had mild liver damage, and some died. Rats, mice, or monkeys that ate smaller amounts of PCBs in food over several weeks or months developed various kinds of health effects, including anemia, acne-like skin conditions, and liver, stomach, and thyroid gland injuries. Other effects caused by PCBs in animals include reductions in the immune system function, behavioral alterations, and impaired reproduction. Some PCBs can mimic or block the action of hormones from the thyroid and other endocrine glands. Because hormones influence the normal functioning of many organs, some of the effects of PCBs may result from endocrine changes. PCBs are not known to cause birth defects. Only a small amount of information exists on health effects in animals exposed to PCBs by skin contact or breathing. This information indicates that liver, kidney, and skin damage occurred in rabbits following repeated skin exposures, and that a single exposure to a large amount of PCBs on the skin caused death in rabbits and mice. Breathing PCBs over several months also caused liver and kidney damage in rats and other animals, but the levels necessary to produce these effects were very high. For more information on how PCBs can affect your health, see Chapters 2 and 3 of the toxicological profile. Studies of workers provide evidence that PCBs were associated with certain types of cancer in humans, such as cancer of the liver and biliary tract. Rats that ate commercial PCB mixtures throughout their lives developed liver cancer. Based on the evidence for cancer in animals, the Department of Health and Human Services (DHHS) has stated that PCBs may reasonably be anticipated to be carcinogens. Both EPA and the International Agency for Research on Cancer (IARC) have determined that PCBs are probably carcinogenic to humans. back to topHow can polychlorinated biphenyls (PCBs) affect children?This section discusses potential health effects from exposures during the period from conception to maturity at 18 years of age in humans. Children are exposed to PCBs in the same way as are adults: by eating contaminated food, breathing indoor air in buildings that have electrical devices containing PCBs, and drinking contaminated water. Because of their smaller weight, children’s intake of PCBs per kilogram of body weight may be greater than that of adults. In addition, a child’s diet often differs from that of adults. A Food and Drug Administration (FDA) study in 1991 estimated dietary intakes of PCBs for infants (6 months) and toddlers (2 years) of less than 0.001 and 0.002 µg/kg/day. Children who live near hazardous waste sites may accidentally eat some PCBs through hand-to-mouth behavior, such as by putting dirty hands or other soil/dirt covered objects in their mouths, or eating without washing their hands. Some children also eat dirt on purpose; this behavior is called pica. Children could also be exposed by playing with old appliances or electrical devices that contain PCBs. It is possible that children could be exposed to PCBs following transport of the chemical on clothing from the parent’s workplace to the home. House dust in homes of workers exposed to PCBs contained higher than average levels of PCBs. PCBs have also been found on the clothing of firefighters following transformer fires. The most likely way infants will be exposed is from breast milk that contains PCBs. Fetuses in the womb are also exposed from the exposed mother. In one study of women exposed to relatively high concentrations of PCBs in the workplace during pregnancy, their babies weighed slightly less at birth than babies born to women exposed to lower concentrations of PCBs. Studies of women who consumed high amounts of fish contaminated with PCBs and other chemicals also had babies that weighed less than babies from women who did not eat fish. Similar observations have been made in some studies of women with no known high exposure to PCBs, but not all studies have confirmed these findings. Babies born to women who ate fish contaminated with PCBs before and during pregnancy showed abnormal responses to tests of infant behavior. Some of these behaviors, such as problems with motor skills and a decrease in short-term memory, persisted for several years. However, in these studies, the women may have been exposed to other chemicals. Other studies suggest that the immune system may be affected in children born to and nursed by mothers exposed to increased levels of PCBs. There are no reports of structural birth defects in humans caused by exposure to PCBs or of health effects of PCBs in older children. It is not known whether PCB exposure can cause in skin acne and rashes in children as occurs in some adults, although it is likely that the same effects would occur at very high PCB exposure levels. Animal studies have shown harmful effects in the behavior of very young animals when their mothers were exposed to PCBs and they were exposed in the womb or by nursing. In addition, some animal studies suggest that exposure to PCBs causes an increased incidence of prenatal death and changes in the immune system, thyroid, and reproductive organs. Studies in monkeys showed that young animals developed skin effects from nursing after their mothers were exposed to PCBs. Some studies indicate that very high doses of PCBs may cause structural birth defects in animals. Children can be exposed to PCBs both prenatally and from breast milk. PCBs are stored in the mother’s body and can be released during pregnancy, cross the placenta, and enter fetal tissues. Because PCBs dissolve readily in fat, they can accumulate in breast milk fat and be transferred to babies and young children. PCBs have been measured in umbilical cord blood and in breast milk. Some studies have estimated that an infant who is breast fed for 6 months may accumulate in this period 6–12% of the total PCBs that will accumulate during its lifetime. However, in most cases, the benefits of breast-feeding outweigh any risks from exposure to PCBs in mother’s milk. You should consult your health care provider if you have any concerns about PCBs and breast feeding. Because the brain, nervous system, immune system, thyroid, and reproductive organs are still developing in the fetus and child, the effects of PCBs on these target systems may be more profound after exposure during the prenatal and neonatal periods, making fetuses and children more susceptible to PCBs than adults. More information regarding children’s health and PCBs can be found in Chapter 3 (Section 3.7) of the toxicological profile. back to topHow can families reduce their risk of expsoure to Polychlorinated biphenyls (PCBs)?If your doctor finds that you have been exposed to significant amounts of polychlorinated biphenyls, ask whether your children might also be exposed. Your doctor might need to ask your state health department to investigate. You and your children may be exposed to PCBs by eating fish or wildlife caught from contaminated locations. Certain states, Native American tribes, and U.S. territories have issued fish and wildlife advisories to warn people about PCB-contaminated fish and fish-eating wildlife. These advisories will tell you what types and sizes of fish and game animals are of concern. An advisory may completely ban eating fish or game or tell you to limit your meals of a certain fish or game type. For example, an advisory may tell you not to eat a certain type of fish or game more than once a month. The advisory may tell you only to eat certain parts of the fish or game and how to prepare or cook the fish or game to decrease your exposure to PCBs. The fish or wildlife advisory may have special restrictions to protect pregnant women, nursing mothers, and young children. To reduce your children’s exposure to PCBs, obey these advisories. Additional information on fish and wildlife advisories for PCBs, including states that have advisories, is provided in Chapter 6 (Section 6.7) and Chapter 8 of the toxicological profile. You can consult your local and state health departments or state natural resources department on how to obtain PCB advisories, as well as other important information, such as types of fish and wildlife and the locations that the advisories apply to. Children should be told that they should not play with old appliances, electrical equipment, or transformers, since they may contain PCBs. Children who live near hazardous waste sites should be discouraged from playing in the dirt near these sites and should not play in areas where there was a transformer fire. In addition, children should be discouraged from eating dirt, and careful handwashing practices should be followed. As mentioned in Section 1.3 of the profile, workplace exposure to PCBs can still occur during repair and maintenance of old PCB transformers; accidents, fires, or spills involving these transformers or other PCB-containing items; and disposal of PCB materials. If you are exposed to PCBs in the workplace, it may be possible to carry them home from work. Your occupational health and safety officer at work can tell you whether the chemicals you work with may contain PCBs and are likely to be carried home on your clothes, body, or tools. If this is the case, you should shower and change clothing before leaving work, and your work clothes should be kept separate from other clothes and laundered separately. back to topIs there a medical test to determine whether I have been exposed to polychlorinated biphenyls (PCBs)?Levels of PCBs in the environment were zero before PCBs were manufactured. Now, all people in industrial countries have some PCBs in their bodies. There are tests to determine whether PCBs are in the blood, body fat, and breast milk. These are not regular or routine clinical tests, such as the one for cholesterol, but could be ordered by a doctor to detect PCBs in people exposed to them in the environment and at work. If your PCB levels are higher than the background levels, this will show that you have been exposed to high levels of PCBs. However, these measurements cannot determine the exact amount or type of PCBs that you have been exposed to, or how long you have been exposed. Although these tests can indicate whether you have been exposed to PCBs to a greater extent than the general population, they do not predict whether you will develop harmful health effects. Blood tests are the easiest, safest, and probably the best method for detecting recent exposures to large amounts of PCBs. Results of such tests should be reviewed and carefully interpreted by physicians with a background in environmental and occupational medicine. Nearly everyone has been exposed to PCBs because they are found throughout the environment, and people are likely to have detectable amounts of PCBs in their blood, fat, and breast milk. Recent studies have shown that PCB levels in tissues from United States population are now declining. Additional information on tests used to determine whether you have been exposed to PCBs can be found in Chapter 3 (Section 3.11) and Chapter 7 (Section 7.1) of the toxicological profile. back to topWhat recommendations has the federal government made to protect human health?The federal government develops regulations and recommendations to protect public health . Regulations can be enforced by law. Federal agencies that develop regulations for toxic substances include the Environmental Protection Agency (EPA), the Occupational Safety and Health Administration (OSHA), and the Food and Drug Administration (FDA). Recommendations provide valuable guidelines to protect public health but cannot be enforced by law. Federal organizations that develop recommendations for toxic substances include the Agency for Toxic Substances and Disease Registry (ATSDR) and the National Institute for Occupational Safety and Health (NIOSH). Regulations and recommendations can be expressed in not-to-exceed levels in air, water, soil, or food that are usually based on levels that affect animals; then they are adjusted to help protect people. Sometimes these not-to-exceed levels differ among federal organizations because of different exposure times (an 8-hour workday or a 24-hour day), the use of different animal studies, or other factors. Recommendations and regulations are periodically updated as more information becomes available. For the most current information, check with the federal agency or organization that provides it. Some regulations and recommendations for PCBs include the following: The EPA standard for PCBs in drinking water is 0.5 parts of PCBs per billion parts (ppb) of water. For the protection of human health from the possible effects of drinking the water or eating the fish or shellfish from lakes and streams that are contaminated with PCBs, the EPA regulates that the level of PCBs in these waters be no greater than 0.17 parts of PCBs per trillion parts (ppt) of water. States with fish and wildlife consumption advisories for PCBs are identified in Chapter 6 (Section 6.7) and Chapter 8 of the toxicological profile. The FDA has set residue limits for PCBs in various foods to protect from harmful health effects. FDA required limits include 0.2 parts of PCBs per million parts (ppm) in infant and junior foods, 0.3 ppm in eggs, 1.5 ppm in milk and other dairy products (fat basis), 2 ppm in fish and shellfish (edible portions), and 3 ppm in poultry and red meat (fat basis). OSHA regulates that workers not be exposed by inhalation over a period of 8 hours for 5 days per week to more than 1 milligram per cubic meter of air (mg/m³) for 42% chlorine PCBs, or to 0.5 mg/m³ for 54% chlorine PCBs. NIOSH recommends that workers not breathe air containing 42 or 54% chlorine PCB levels higher than 1 microgram per cubic meter of air (µg/m³) for a 10-hour workday, 40-hour workweek. EPA requires that companies that transport, store, or dispose of PCBs follow the rules and regulations of the federal hazardous waste management program. EPA also limits the amount of PCBs put into publicly owned waste water treatment plants. To minimize exposure of people to PCBs, EPA requires that industry tell the National Response Center each time 1 pound or more of PCBs have been released to the environment. For more information on federal and state regulations and guidelines for PCBs, see Chapter 8 of the toxicological profile. back to topWhat are other names for polychlorinated biphenyls?
What are the common uses of PCBs?
What happens when PCBs enter the environment?PCBs do not readily break down in the environment and therefore may persist for a very long time. They can easily cycle between air, water, and soil.
What are the sources, routes, and types of exposure to PCBs?
What are the effects of exposure to PCBs?
What are the safety guidelines for exposure to PCBs?
What are the minimal risk levels for exposure to PCBs?An MRL is an estimate of the daily human exposure to a hazardous substance that is likely to be without appreciable risk of adverse non-cancer health effects over a specified duration of exposure. Below is a comparison of pcb exposure routes
What are the most important or common mediating factors?The factors that determine how severe the health effects are exposure to PCBs include:
How is exposure to PCBs managed and treated?No specific treatment for PCB toxicity is currently available. However, decontamination and supportive treatment are advised.
How does the body eliminate PCBs?
Is there a test to see if my child or I have been exposed to PCBs?There are tests to determine whether PCBs are in the blood, body fat, and breast milk. These are not regular or routine clinical tests, such as the one for cholesterol, but could be ordered by a doctor to detect PCBs in people exposed to them in the environment and at work.
Current research needs
Where can I get more information?ATSDR. Toxicological Profile for Polychlorinated Biphenyls. Atlanta: Agency for Toxic Substances and Disease Registry, 2000 November. Available at: www.atsdr.cdc.gov/toxprofiles/tp17.html. ATSDR, Substance Specific Priority Data Needs, Atlanta: Agency for Toxic Substances and Disease Registry, 2006 March. Available at: www.atsdr.cdc.gov/pdns/index.html. EPA. Polychlorinated Biphenyls Home Page. Washington, DC: Environmental Protection Agency. 2006 February 15. Available at: www.epa.gov/opptintr/pcb/. EPA. Information about polychlorinated biphenyls. Washington, DC: Environmental Protection Agency. Available at: http://www.epa.gov/wastes/hazard/tsd/pcbs/. CDC. Third national report on human exposure to environmental chemicals. Atlanta: Centersfor Disease Control and Prevention. 2005 July 21. Available at: www.cdc.gov/exposurereport/. back to topReferencesAgency for Toxic Substances and Disease Registry (ATSDR). 2000. Toxicological profile for polychlorinated biphenyls (PCBs). Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service. back to top
Complete PCB Toxicological Information
POLYCHLORINATED BIPHENYLS Human Health Effects:
Evidence for Carcinogenicity: Classification of carcinogenicity: 1) evidence in humans: limited; 2) evidence in animals: sufficient. Overall summary evaluation of carcinogenic risk to humans is Group 2A: The agent is probably carcinogenic to humans. /Polychlorinated biphenyls; from table/ CLASSIFICATION: B2; probable human carcinogen. BASIS FOR CLASSIFICATION: A 1996 study found liver tumors in female rats exposed to Aroclors 1260, 1254, 1242 and 1016 and in male rats exposed to 1260. These mixtures contain overlapping groups of congeners that, together, span the range of congeners most often found in environmental mixtures. Earlier studies found high, statistically significant incidences of liver tumors in rats ingesting Aroclor 1260 or Clophen A 60 (Kimbrough et. al., 1975; Norback and Weltman, 1985; Schaeffer et. al., 1984). Mechanistic studies are beginning to identify several congeners that have dioxin-like activity and may promote tumors by different modes of action. PCBs are absorbed through ingestion, inhalation, and dermal exposure, after which they are transported similarly through the circulation. This provides a reasonable basis for expecting similar internal effects from different routes of environmental exposure. Information on relative absorption rates suggests that differences in toxicity across exposure routes are small. The human studies are being updated; currently available evidence is inadequate, but suggestive. HUMAN CARCINOGENICITY DATA: Inadequate. ANIMAL CARCINOGENICITY DATA: Sufficient.
Human Toxicity Excerpts: IN SURVEY OF 3 GROUPS OF WORKERS EXPOSED TO POLYCHLORINATED BIPHENYLS (PCBS) SERUM PCB CONCN WERE QUANTITATED AS LOWER PCB & HIGHER PCB. SERUM LOWER PCB & HIGHER PCB CONCN WERE MANY TIMES GREATER AMONG WORKERS EMPLOYED IN POWER CAPACITOR MANUFACTURING THAN AMONG GENERAL POPULATION. POSITIVE CORRELATIONS OF SYMPTOMS SUGGESTIVE OF MUCOUS MEMBRANE & SKIN IRRITATION, MALAISE & ALTERED SENSATION WERE NOTED WITH INCR CONCN OF SERUM PCB. NO CLINICAL ABNORMALITIES ATTRIBUTABLE TO EXPOSURE TO PCB WERE OBSERVED. SERUM CONCN WERE POSITIVELY CORRELATED WITH INCR OF GLUTAMIC-OXALACETIC TRANSAMINASE, SERUM GAMMA-GLUTAMYL TRANSPEPTIDASE & PLASMA TRIGLYCERIDE, & INVERSELY CORRELATED WITH PLASMA HIGH DENSITY LIPOPROTEIN-CHOLESTEROL. Deaths that occurred up to 5 1/2 yr after first exposure to PCB's ... were reported. Nine (41%) of 22 deaths were due to malignant neoplasms. Three of the tumors occurred in the stomach, one in the liver, two in the lung and one in the breast, and two were malignant lymphomas. A significant correlation was found between plasma levels of polychlorinated biphenyls(PCBs) in mothers occupationally exposed to these cmpd and the PCB milk levels. It has been observed that if these mothers nursed their babies for more than three months, the PCB levels in the infants exceeded that of their mothers. These cmpd were subsequently retained in the children for many years. ... /RESPONSES TO PCBS/: ACNE; HYPERPIGMENTATION OF SKIN; HYPERACTIVE MEIBOMIAN GLANDS; CONJUNCTIVITIS; EDEMA OF EYELIDS; SUBCUTANEOUS EDEMA; KERATIN CYSTS IN HAIR FOLLICLES; HYPERPLASIA OF HAIR FOLLICLE EPITHELIUM; HEPATIC HYPERTROPHY; DECR NUMBER OF RED BLOOD CELLS; DECR HEMOGLOBIN; SERUM HYPERLIPIDEMIA; LEUCOCYTOSIS. Disease/Syndrome Chloracne Category Skin Disease Acute/Chronic Chronic Biomedical References Search PubMed Comments Chloracne appears as comedones and straw-colored cysts on the face. Cysts may also occur in the axillae and groin. The condition usually appears within 2 months of exposure and resolves within 4-6 months after cessation of exposure. Chloracne is associated with dry skin, conjunctivitis, scarring, peripheral neuropathy, and liver abnormalities. Chemicals that can cause chloracne include: dioxin, pentachlorophenol, PCBs, PBBs, furans, polyhalogenated naphthalenes (polychloronaphthalenes), DDT (crude trichlorobenzene), Propanil, Methazole (both tetrachloroazoxybenzenes), 1,2,3,4-Tetrachlorobenzene, and Dichlobenil. [Rosenstock, p. 714-5] Acneform lesions may appear as early as 1 to 3 weeks after dioxin exposure. Most cases of chloracne resolve within 1 to 3 years. There is no acceptable dose-response model for chloracne in exposed human populations. Chloracne may develop weeks or months after exposure and may be dependent upon individual predisposition. [ATSDR Case Studies: PCB Toxicity] Latency/Incubation Weeks to months Diagnostic Clinical ICD-9 Code 706.1 Reference Link CCOHS - Occupational Acne Image Chloracne. DermNet NZ Related Information in Haz-Map Symptoms/Findings Symptoms/Findings associated with this disease: acne pustule Job Tasks High risk job tasks associated with this disease: Remove or replace PCB contaminated fluid in transformers Work in confined space Work with toxic chemicals that could be spilled or released Agents Hazardous agents that cause this disease: Dermatotoxins that cause chloracne A leaking heat exchanger in a chemical plant discharged polychlorinated biphenyl (PCB) vapors. No employees worked routinely at the point of leakage, but breathing zone levels in work areas were found to be 0.1 mg/cu m. The period of exposure was 19 months. Seven of 14 exposed workers developed mild to moderate chloracne after exposure durations of 5-14 months. Liver function tests showed normal serum bilirubin, 24 and 48 hr cephalin flocculations, thymol turbidities, and serum alkaline phosphatase activities in six of the seven workers, but borderline increases in cephalin flocculation and thymol turbidity in the seventh. After 13 months, the thymol turbidity but not the cephalin flocculation had improved. An analysis of the health effects of polychlorinated biphenyls (PCB) on eight laboratory workers involved in testing dielectric fluids was made. ... The workers, all males 25 to 49 yr of age, had been employed 2.5 to 18 yrs. Breathing zone, point source, and general work area samples were collected on three separate occasions. The ranges were: breathing zone, 0.014 to 0.073 mg/cu m; point source (near an oven), 0.042 to 0.264 mg/cu m; and room area, 0.013 to 0.15 mg/cu m. Blood concns were 36 to 286 ppb which is substantially above the range in several studies of general populations. Workers complained of dry, sore throat (6/8), skin rash (3/8), gastrointestinal disturbances (3/8), and eye irritation and headache (2/8). Examination disclosed one patient with skin rash, two with nasal irritation, one showing rales, and four with high blood pressure, but no abnormalities in liver function. Irregular menstrual cycles, early abortions and the birth of small, hyperpigmented and hyperkeratotic infants have been observed. Spirometric findings in a retrospective cohort of 136 capacitor workers with occupational exposure to polychlorinated biphenyls (PCBs) during active use (1976) and after the PCB ban (1979 and 1983) are reported. Quantitative exposure levels are not known. Subjects were categorized as having high, medium, or low exposure depending primarily on the extent of dermal contact. Mean 1979 serum PCB levels were elevated 35 to 40 times the normal level. Duration of employment ranged from 1-35 yr. Obstructive impairment was consistently found in 15% of the workers in 1976 and 1979. A history of respiratory illness and reduced FEV 1/FVC was correlated in a dose-response fashion with PCB exposure category and serum PCB levels in females in 1976 but the association disappeared in 1979. It is not clear whether the association held when controlled for smoking. There was no association between PCB exposure and abnormal pulmonary function tests in males. PCBS ARE LIVER TOXINS & CAUSE CHLORACNE & POSSIBLY PERIPHERAL NEUROPATHY IN MAN. The first documentation of human effects as a result of ingestion of PCBs was derived from the Japanese poisoning incident that occurred in 1968. The victims suffered an acute toxicosis from consuming rice oil contaminated with an industrial oil, Kanechlor-400, consisting of a mixture of polychlorinated biphenyls (PCB), polychlorinated dibenzofurans (PCDF), and polychlorinated quinones (PCQ). The average total amount of PCBs consumed was estimated to be approximately 2 g, with approximately 0.5 g being the least total amount consumed by an affected group of some 325 people at the time. ... The most notable symptoms of Yusho among 189 patients included dark brown pigmentation of nails and skin, follicular accentuation, acneform eruptions, increased eye discharge, increased sweating at the palms and feeling of weakness. ... A mass outbreak of a peculiar skin disease /including pigmentation and acne from eruptions/ was recorded in Taichung and Changwa in Central Taiwan. The cause of the disease was later identified to be the ingestion of rice bran oil contaminated with polychlorinated biphenyls (PCBs), and there were > 1900 victims. Blood PCB levels of 66 affected persons ranged from 11-720 ppb (mean 49 ppb) at approx 9-12 months after consumption of the PCB-contaminated oil. Polychlorinated biphenyl blood residues were measured in 29 infertile males and in 14 matched control subjects at a hospital in Jerusalem, Israel. The patients' ages ranged from 25 to 45 years. The patients exhibited one or more impaired semen characteristics such as decreased spermatozoa count, lower sperm motility, or a greater proportion of morphologically abnormal spermatozoa. The control group, matched by age and smoking habits, consisted of randomly selected patients with minor illnesses. Each of them had at least one child not older than two years of age. None of the subjects had a history of occupational exposure to organochlorine compounds. The polychlorinated biphenyl levels were measured by GC-ECD. The mean concentration of total polychlorinated biphenyls in the infertile patients was 11.21 + or - 13.48 ng/g blood serum (range 0 to 64.2 ng/g). The control subjects had a mean concentration of 7.94 + or - 14.69 ng/g (range 0 to 47.3 ng/g). A retrospective cohort mortality study of workers exposed to polychlorinated biphenyl (PCBs) in two plants manufacturing electrical capacitors was reported in 1981. The study was conducted primarily to examine the risk of cancer mortality associated with exposure to PCBs: due to the availability of animal data, liver cancer was the disease of most interest. Because of the small number of deaths and a relatively short observation period the study was inconclusive. Therefore, the study was updated by adding 7 yr of observation increasing the number of deaths in the study cohort from 163 to 295. Mortality from all causes was found to be lower than expected (295 observed versus 318 expected deaths) as well as mortality from all cancers (62 observed versus 80 expected deaths). A statistically significant excess in deaths was observed in the category that includes cancer of the liver (primary and unspecified), gall bladder, and biliary tract (5 observed versus 1.9 expected; p< 0.05). Most of this excess was observed in women employed in one plant. The possibility of polychlorinated biphenyl-induced porphyria after transplacental exposure was investigated using children born to mothers exposed to contaminated rice oil in central Taiwan in 1979. The exposure was to a mixture of thermally degraded polychlorinated biphenyls, polychlorinated quaterphenyls, & polychlorinated dibenzofurans, which had become mixed with the oil during processing. Women who became pregnant had children with high perinatal mortality and a dysmorphic syndrome. Seventy four controls and 12 siblings of the exposed children were included in the study. Four of the transplacentally exposed children, 2 controls and 1 sib had a type B hepatic porphyria; total porphyrin excretion was elevated in the exposed children as a group (95 ug/l, exposed; 81 ug/l, control); and 8 of the 75 exposed children and 2 controls had total urinary porphyrin concentrations of >200 ug/l. The children did not appear to have symptoms directly attributable to porphyria, but a mild disturbance in porphyrin metabolism appeared to be related to their intrauterine exposure. People occupationally exposed to PCB's have relatively high PCB residue levels. Digestive symptoms such as abdominal pain, anorexia, nausea, vomiting, jaundice, with rare cases of coma and death, may occur. At autopsy, acute yellow atrophy of the liver was found in lethal cases. ... Neurological symptoms such as headache, dizziness, depression, nervousness ... and other symptoms such as fatigue, loss of weight, loss of libido and muscle and joint pains were found in various percentages of exposed people. ... By the study of PCB-associated diseases in the general population, pathological pregnancies (toxemia of pregnancy, abortions, stillbirths, underweight births, etc) were frequently associated with increased PCB serum levels. ... Mother's milk contaminated with PCB's appears to be a source of exposure for infants. Developmental abnormalities have been observed in PCB-intoxicated infants. Premature eruption of teeth was observed ... and larger frontal and occipital fontanelles, exophthalmos and the maintenance of an abnormally wide sagittal suture were observed. ... Skin and mucous membrane changes; swelling of the eyelids, burning of the eye, and excessive eye discharge, burning sensation and edema of face and hands, simple erythematous eruptions with pruritus, acute eczematous contact dermatitis, chloracne, hyperpigmentation of skin and mucous membranes, discoloration of finger nails and thickening of the skin were reported. Dental records were studied and dental exams given to children living in Taiwan transplacentally exposed to polychlorinated biphenyls (PCB) (Yu-Cheng babies) as confirmed by epidemiological studies in the early 1980s. Nine school aged Yu-Cheng males and 9 females were compared to an unexposed reference group of 26 males and 18 females on the prevalence of missing permanent teeth germ while taking congenital factors into account. Among 9 transplacental Yu-Cheng girls, 4 were missing permanent teeth germ due to congenital factors. Among the 18 girls in the reference group, none were missing permanent teeth germ due to congenital factors. Among 9 transplacental Yu-Cheng boys, 1 was missing permanent teeth germ due to congenital factors. Among the 26 boys in the reference group, 1 was missing permanent teeth germ due to congenital factors. A job exposure matrix was developed linking the work tasks in the Swedish National Census of population 1960 to exposure to 50 single agents or groups of substances, including polychlorinated biphenyls. All 1,905,660 men (ages 20-64 yr) in 1960, reporting themselves as gainfully employed in the Census, were observed for the occurrence of urothelial cancer during the 1961-1979 period by linkage to the National Swedish Cancer Registry. Only subjects in 1 work task, electricians in electric power stations, were assigned exposure to polychlorinated biphenyls with a moderate predictive value. The relative risk (with 95% confidence interval) for this group was 1.3 (1.0-1.8) for urinary bladder cancer. In Taiwan in 1979, rice oil contaminated with polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans was ingested by approx 2000 people. Blood samples were taken from 36 women who were potentially exposed, and 24 non-exposed women (controls). The frequency of sister chromatid exchanges in lymphocytes from their heparinized whole blood was assessed after culturing cells in the presence or absence of 40 uM alpha-naphthoflavone for 72 hr. There was no significant difference in baseline sister chromatid exchanges for PCB exposed compared to the control group (7.29 vs 7.61). In contrast, addition of alpha-naphthoflavone resulted in a dramatic induction of sister chromatid exchange frequencies in PCB exposed lymphocytes (p < 0.01). PCB exposed frequencies increased to 10.75, while those of the unexposed group only increased to 8.85. Agent ... Polychlorinated biphenyls. Suspected human sites ... liver. /from table/ Mixtures of PCBs (e.g., Aroclors) have been commonly used to evaluate the immunotoxicity of PCBs and have been reported to suppress immune responses and decrease host resistance. Adverse health effects in humans have occurred from exposure to all of them. /Dioxin, polychlorinated biphenyls, and dibenzofurans/ Children in the top 5 percent for PCB exposure showed delayed maturation of motor abilities. There is one report of an increase in melanoma in PCB-exposed workers. ... Association between the maternal PCB level and the number and type of infections that occurred in the infants first 4 months of life. Visual recognition memory was reduced at 7-month follow-up of the offspring of mothers exposed to PCBs in contaminated fish. Yusho in 1968 ... and Yu-Cheng in 1979 ... affected more than 2000 people who ingested cooking rice oil contaminated with PCBs and related compounds. The disease was especially severe in children and with exposure in utero. The clinical syndrome included abnormal liver function tests, hepatomegaly ..., and electron microscopic alterations in the endoplasmic reticulum and mitochondria. Selected adverse human health effects reportedly due to chemical toxicants. Chemical- polychlorinated biphenyls (PCBs) ... Organ- skin ... Effect- folliculitis and acneform dermatosis /from table/ Drugs considered to be proven human teratogens ... Polychlorinated biphenyls (PCBs) /from table/ Toxic effects of PCBs include chloracne, ocular irritation, arthritis, gastrointestinal symptoms, and hepatotoxicity. Polychlorinated biphenyls (PCB; Arochlor, Inerteen, Kanechlor, Pyranol) have accidentally become widely distributed in food, especially in Japan where contaminated cooking oil consumed by 1000 people in 1968 caused a condition known as Yushu, and later in Taiwan where a similar epidemic occurred. The clinical characteristics were chloracne, brown pigmentation of skin, nails, and palpebral and bulbar conjunctiva, swelling and pigmentation of the eyelids, and eye discharge, particularly from hypersecretion from the Meibomian glands. Babies born to mothers with this type of poisoning likewise showed palpebral and conjunctival pigmentation, cheesy secretion in the conjunctival sac, and also exophthalmus. An enlarged liver and increased absolute and relative liver weights are commonly reported as gross effects of PCB administration. Acute and long-term exposures to PCBs have been reported to cause neurological and unspecific psychological or psychosomatic effects, such as headache, dizziness, nausea, depression, sleep and memory disturbances, nervousness, fatigue, and impotence. Biopsy skin samples showed hyperkeratosis, dilation of the follicles, and an accumulation of melanin in the basal cells of the epidermis; melanin granules have also been observed in biopsy samples of the conjunctiva. Oedema of the arms and legs was also seen in some patients. Skin exposure is important in the case of long-term exposure, even though the ambient concentrations may be low. ... Skin may be responsible for up to 20% of the total body uptake of PCBs is workers exposed ... .
Skin, Eye and Respiratory Irritations: Irritating to skin and eyes.
Drug Warnings: Food and Environmental Agents: Reported Sign or Symptom in Infant or Effect on Lactation: Polychlorinated biphenyls and polybrominated biphenyls: Lack of endurance, hypotonia, sullen, expressionless faces. /From Table 7/
Medical Surveillance: Medical records should be kept for the entire length of employment of each worker and for the following 30 yr. PRECAUTIONS FOR "CARCINOGENS": Whenever medical surveillance is indicated, in particular when exposure to a carcinogen has occurred, ad hoc decisions should be taken concerning ... /cytogenetic and/or other/ tests that might become useful or mandatory. /Chemical Carcinogens/ The assessment of PCB exposure can be accomplished through measurement of specific PCB's. However, due to the interference of whole blood components, serum or plasma is the preferred specimen for analysis. Blood Reference Ranges: Normal - less than 5 mg/l; Exposed - not established; Toxic - not established. Serum or Plasma Reference Ranges: Normal - less than 10 mg/l; Exposed - not established; Toxic - not established. Urine Reference Ranges: Normal - not established; Exposed - not established; Toxic - not established. The assessment of PCB exposure can be accomplished through measurement of PCB's in adipose tissue, due to accumulation in this lipophilic tissue. This measurement may be useful for assessing the total body burden of PCB's. The normal background level of PCB's in adipose tissue is approx 1 to 2 ppm (1 to 2 mg/l). There are three general categories of liver function tests: biochemical tests (serum enzyme activity, serum alkaline phosphatase, lactate dehydrogenase and bilirubin), tests of synthetic function (serum albumin, prothrombin time, alpha fetoprotein and serum ferritin), and clearance tests (bromsulphalein, indocyanine green, antipyrine test, aminopyrine breath test, caffeine breath test, D-Glucaric acid, 6-beta-hydroxycortisol and bile acids). Evaluation of Peripheral Neuropathy: Nerve conduction study; Electromyography; Quantitative sensory testing; Thermography. Evaluation of Central Nervous System Effects: Evaluation of CNS effects can be performed through neuropsychological assessment, which consists of a clinical interview and administration of standardized personality and neuropsychological tests. The areas that the neuropsychology test batteries focus on include the domains of memory and attention; visuoperceptual, visual scanning, visuospatial, and visual memory; and motor speed and reaction time. There is limited data on which components of the test batteries are best indicators of early CNS effects. Evaluation of Cranial Neuropathies: Evaluation of cranial nerve damage, as evidenced by symptoms such as loss of balance, visual function, smell, taste, or sensation on the face, can be accomplished through a physical examination focusing on tests such as: Smell Assessment ... Visual Assessment ... Facial and Trigeminal Nerve Assessment ... Vestibular Assessment ... Hearing Assessment.
Populations at Special Risk: Persons with skin diseases and chronic liver diseases and women of child-bearing age /are at special risk in facilities/ manufacturing or using PCBs. Those groups at particular risk for PCB exposure include ... individuals consuming large amounts of contaminated fish, such as sport fishermen, and nursing infants who, per kg body weight, may accumulate significant body burdens from the levels in human breast milk.
Probable Routes of Human Exposure: ... Environmental contamination may be a significant source of human exposure. Likely routes of exposure for the general population are water and particularly food, while inhalation and dermal contact are likely to be more significant routes in occupational exposure. Serum samples from 285 4-yr-old Michigan children were evaluated for levels of 11 environmental contaminants. Polychlorinated biphenyls (PCBs) were found in half the samples tested. Nursing (mothers' milk) was the principal source of these exposures. Congener-specific analysis documented the presence of at least one highly toxic PCB congener, 2,3',4,4',5-pentachlorobiphenyl. Mothers were exposed to PCBs through their consumption of Lake Michigan sport fish or farm products (milk or meat) contaminated with PCBs as ascertained by the Michigan Department of Public Health. HUMAN EXPOSURE TO SMALL AMT OF PCB'S IS WIDESPREAD AS A RESULT OF ENVIRONMENTAL CONTAMINATION & HIGH STABILITY OF THESE CMPD. Toxic non-, mono- and di-ortho coplanar PCB congeners were determined in terrestrial mammals (human, cat and dog), a coastal marine mammal (finless porpoise), and marine mammals (Dall's porpoise, Baird's beaked whale, and the killer whale). Total PCBs were 1.0 ug/g (human), 2.0 (cat), 0.10 (dog), 320 (finless porpoise), 8.6 (Dall's porpoise), 2.3 (Baird's beaked whale), and 370 ug/g wet wt (killer whale). The concn of coplanar PCBs were found to be higher in the order of di-ortho > mono-ortho > non-ortho congeners and were significantly higher than the levels of toxic dioxins and furans. The geographical distribution of these chemicals based on the relative abundance of coplanar PCB congeners with reference to total PCBs did not vary in terrestrial, coastal and open ocean mammals, whereas that of polychlorinated dibenzofurans and polychlorinated dibenzodioxins apparently decr from land to ocean. 2,3,7,8-Tetrachlorodibenzo-p-dioxin toxic equivalent analysis revealed that higher aquatic predators such as cetaceans receive a greater toxic threat from 3,3',4,4',5- and 2,3,3',4,4'-pentachlorobiphenyls than polychlorinated dibenzofurans and polychlorinated dibenzodioxins. Dermal exposure is important for workers involved with handling PCB containing electrical equipment, spills or waste-site materials and for swimmers in polluted water(1). Exposure through consumption of contaminated fish may be especially important. Large exposure may be characteristic of PCB fires(1). It was estimated that approximately 12,000 USA workers were potentially exposed to PCBs annually from 1970-1976(1). A review of occupational exposure data found that workroom air of factories using PCBs for manufacturing may vary from 0.1 to 10.5 mg/cu m(2). Concentrations of PCBs in the air during different manufacturing processes are as follows: capacitor mfg (80-275 ug/cu m), electrical equipment mfg (0-264 ug/cu m), transformer inspection (0.4-9 ug/cu m)(3). Airborne concentrations in the room of overheated transformers containing PCBs were found to be 50-90 ug/cu m one day after the overheating occurred(4). NIOSH (NOES Survey 1981-1983) has statistically estimated that 459 workers, number of female workers unreported, were potentially exposed to PCBs in the US(1). Occupational exposure to PCBs may occur through inhalation and dermal contact with this compound at workplaces where PCBs are still present(such as hazardous waste sites)(SRC). The general population may be exposed to PCBs via ingestion of food(2), particularly fish(3-5), and drinking water(6-8) contaminated with PCBs(SRC). The potential levels of PCBs in indoor air may be from 2 to 10 times higher than typical levels found in outdoor air due in part to the presence of PCB-containing transformers and electrical parts(1).
Body Burden: /IN 1970/ ... THE MEAN PCB LEVEL IN HUMAN MILK IN TWO CALIFORNIA CITIES WAS ABOUT 0.06 UG/ML OF WHOLE MILK. ... ANALYSIS OF LIPID FRACTION OF 80 SAMPLES OF HUMAN MILK FROM VARIOUS AREAS OF US SHOWED THAT ALL EXCEPT 2 HAD CONCN ... FROM 0.4-10.6 UG/G. THE AVERAGE CONCN IN ALL SAMPLES WAS APPROX 1.7 UG/G. /POLYCHLORINATED BIPHENYLS/ FORTY-THREE PERCENT OF 723 PLASMA SAMPLES FROM PERSONS IN SOUTH CAROLINA NOT OCCUPATIONALLY EXPOSED TO PESTICIDES WERE FOUND TO CONTAIN PCBS, WITH A MAXIMUM OF 0.029 UG/ML. /POLYCHLORINATED BIPHENYLS/ PCB CONTAMINATION IS FOUND TO BE ALMOST UNIVERSAL, INCLUDING HUMAN MILK, HUMAN ADIPOSE TISSUE, & BRAIN & LIVER OF SMALL CHILDREN. Polychlorinated biphenyl blood residues were measured in 29 infertile males and in 14 matched control subjects at a hospital in Jerusalem, Israel. The patients' ages ranged from 25 to 45 years. The patients exhibited one or more impaired semen characteristics such as decreased spermatozoa count, lower sperm motility, or a greater proportion of morphologically abnormal spermatozoa. The control group, matched by age and smoking habits, consisted of randomly selected patients with minor illnesses. Each of them had at least one child not older than two years of age. None of the subjects had a history of occupational exposure to organochlorine compounds. The polychlorinated biphenyl levels were measured by GC-ECD. The mean concentration of total polychlorinated biphenyls in the infertile patients was 11.21 +/- 13.48 ng/g blood serum (range 0 to 64.2 ng/g). The control subjects had a mean concentration of 7.94 +/- 14.69 ng/g (range 0 to 47.3 ng/g). Mean PCB concns ranging from 0.35 to 8.3 mg/kg have been detected in human fat of subjects from 12 different nations, including the USA(1). PCB levels of 19-24 ug/kg and 57.2-74.2 mg/kg were found in milk and fatty tissue, respectively, of Norwegian women(2). Human adipose tissue of 46 Japanese males and 46 females was found to contain mean levels of 3.29 and 2.75 ppm PCB in 1981(3). Mean and median concn of 5 and 4 ppb, respectively, were detected in the blood of 738 new employees of a CA electric company; these values are comparable to previously published values for PCB concn in people without occupational exposure(4). Fifty samples of human milk from Finland were found to contain mean PCB levels of 0.016 and 0.45 mg/kg in whole milk fat, respectively(5). Analysis of serum specimens of 1462 Michigan residents in 1978 found mean PCB levels of 2-10 ppb(6). The burden of PCBs in human fat has been found to range between 500 and 1500 ppb(7). EPA human monitoring program found PCB body pattern to be similar irrespective of source for non-occupationally exposed humans; PCB pattern resembled Aroclor 1260(1). The 2,3,4,5-PCBs are preferentially enriched in human milk with a least 2 rings substituted (>Cl4). Thus the PCB congeners from Aroclor 1016 would not be major contributors (only for Aroclor 1016, 1221)(1).
Average Daily Intake: AIR INTAKE: (assume typical ambient air concn of 5 ng/cu m)= 100 ng; WATER INTAKE: Predominant source of PCB exposure in the adult male when drinking water levels exceed 1.0 ug/l(2). FOOD INTAKE: (assume 70 kg body wt)= 210-560 ng based on monitoring data for years 1980-1982(1). AIR INTAKE: (assume 0.02 ug PCB/m cu, 16 hrs indoors) - 0.05 ug/kg/day(1). WATER INTAKE: Predominant source of PCB exposure in the adult male when drinking water levels exceed 1.0 ug/l(1). FOOD INTAKE: 0.01 ug/kg/day(1).
Emergency Medical Treatment:
Emergency Medical Treatment: Antidote and Emergency Treatment: Basic Treatment: Establish a patent airway. Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 l/min. for eye contamination, flush eyes immediately with water. Irrigate each eye continuously with normal saline during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 ml/kg up to 200 ml of water for dilution if the patent can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . Cover skin irritation with dry sterile dressings after decontamination. /PCBs, PBBs, PCDFs, and related compounds/ Advanced Treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious or in severe respiratory distress. Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start an IV with lactated Ringer's /SRP: "To keep open", minimal flow rate/. Watch for signs of fluid overload. Use proparacaine hydrochloride to assist eye irrigation ... . /PCBs, PBBs, PCDFs, and related compounds/ If PCB-containing substances are ingested, induce vomiting if the patient is conscious. Activated charcoal has not been proven beneficial, but is not contraindicated. ... There are no known methods of reducing reserves of PCBs in lipid tissues ... Crash diets risk mobilizing PCBs stored in fat. Patients ... encouraged to avoid exposure to other hepatotoxins such as antibiotics ..., alcohol, and chlorinated solvents.
Animal Toxicity Studies:
Evidence for Carcinogenicity: Classification of carcinogenicity: 1) evidence in humans: limited; 2) evidence in animals: sufficient. Overall summary evaluation of carcinogenic risk to humans is Group 2A: The agent is probably carcinogenic to humans. /Polychlorinated biphenyls; from table/ CLASSIFICATION: B2; probable human carcinogen. BASIS FOR CLASSIFICATION: A 1996 study found liver tumors in female rats exposed to Aroclors 1260, 1254, 1242 and 1016 and in male rats exposed to 1260. These mixtures contain overlapping groups of congeners that, together, span the range of congeners most often found in environmental mixtures. Earlier studies found high, statistically significant incidences of liver tumors in rats ingesting Aroclor 1260 or Clophen A 60 (Kimbrough et. al., 1975; Norback and Weltman, 1985; Schaeffer et. al., 1984). Mechanistic studies are beginning to identify several congeners that have dioxin-like activity and may promote tumors by different modes of action. PCBs are absorbed through ingestion, inhalation, and dermal exposure, after which they are transported similarly through the circulation. This provides a reasonable basis for expecting similar internal effects from different routes of environmental exposure. Information on relative absorption rates suggests that differences in toxicity across exposure routes are small. The human studies are being updated; currently available evidence is inadequate, but suggestive. HUMAN CARCINOGENICITY DATA: Inadequate. ANIMAL CARCINOGENICITY DATA: Sufficient.
Non-Human Toxicity Excerpts: PCB ADMIN HAS BEEN FOUND TO RESULT IN INCREASED SYNTHESIS, HEPATIC CONTENT & EXCRETION OF PORPHYRINS IN RATS, QUAILS & CHICKENS; & THIS HAS BEEN ASSOCIATED WITH AN INCR IN LIVER MITOCHONDRIAL GAMMA-AMINOLEVULINIC ACID SYNTHETASE. The carcinogenicity of polychlorinated biphenyls was shown in animal, experimentally exposed. Benign and malignant liver cell tumors, lymphomas and leukemias, and carcinomas of the gastrointestinal tract were obtained. EXPOSURE OF RATS, RABBITS, MONKEYS, CHICKS AND RAINBOW TROUT TO PCBS RESULTED IN INCREASED ACTIVITY OF ... URIDINE DIPHOSPHOGLUCURONOSYLTRANSFERASE & NITROREDUCTASE, OR A SIGNIFICANT INCR IN THE LEVEL OF CYTOCHROME P450. EGGSHELL THINNING, LOSS OF REPRODUCTIVE ABILITY, OR BOTH HAVE BEEN ATTRIBUTED ... TO PCBS /IN BIRDS/. ISOMERICALLY PURE PCBS WERE TESTED AS INDUCERS OF HEPATIC DRUG-METABOLIZING ENZYMES IN THE RAT. THE CHLORINATED BIPHENYL ISOMERS CAN BE CATEGORIZED INTO 2 DISTINCT GROUPS OF INDUCERS, WHILE COMMERCIAL PCB MIXT HAVE CHARACTERISTICS OF BOTH GROUPS. BIPHENYLS CHLORINATED SYMMETRICALLY IN BOTH THE META AND PARA POSITIONS INCREASE THE FORMATION OF CYTOCHROME P448, BUT DECREASE THE AMINOPYRINE N-DEMETHYLASE ACTIVITY. BIPHENYL ISOMERS CHLORINATED IN BOTH THE PARA AND ORTHO POSITIONS INDUCE THE FORMATION OF CYTOCHROME P450 AND N-DEMETHYLASE ACTIVITY. ISOMERS WHICH ARE CHLORINATED IN ONLY 1 RING, OR ARE CHLORINATED IN BOTH RINGS BUT NOT IN THE PARA POSITIONS, HAVE VERY LITTLE ACTIVITY AS INDUCERS OF LIVER ENZYMES. The most consistent pathological changes occurring in mammals after polychlorinated biphenyls (PCB) exposure are in the liver. In rats, rabbits, and guinea pigs ... fatty deposits after acute injections and similar changes in rabbits and guinea pigs after dermal application /were observed/. In feeding experiments, marked fatty metamorphosis was noted in guinea pig liver with intracellular hyaline bodies observed in rats. Less striking changes were noted in the kidneys, lung, adrenals, and heart of guinea pigs. Rats exposed repeatedly to dietary PCBs showed increased liver weights. Hepatic microsomal activity was elevated by single large doses of Aroclor 1242. Monkeys given 300 ppm for 90 days developed alopecia, chloracne, subcutaneous edema, liver hypertrophy, and hypertrophy and hyperplasia of the gastric mucosa. Animal studies have shown that polychlorinated biphenyls (PCBs) can cross the placental barrier and are excreted in the mother's milk. GROUPS OF 10 MALE & 10 FEMALE 3-4-WEEK-OLD SHERMAN RATS WERE FED 0, 20, 100, 500 OR 1000 MG AROCLOR 1260/KG DIET ... SEVERAL ... GIVEN THE TWO HIGHEST DOSE LEVELS DIED BEFORE 6 MO. ... LESIONS ... DESCRIBED AS ADENOFIBROSIS OF LIVER OCCURRED IN 2 MALES FED 1000 MG/KG & IN 1, 1 AND 4 FEMALES FED 100, 500, AND 1000 MG/KG ... . Certain substitution patterns are believed to influence the biological activities of chlorobiphenyls. The presence of two adjacent carbon atoms without chlorine substitution in one or both rings is believed to facilitate metabolism because it permits the formation of arene oxide intermediates. Essentially all chlorobiphenyls with five or fewer chlorine atoms have at least one pair of adjacent unsubstituted carbon atoms because of the rarity of 3,5-substitution in the natural mixtures. ... Chlorobiphenyls with three or four chlorine atoms in the ortho-positions (2- and 6-) are more easily metabolized by humans than those with only one or two ortho- chlorines. ... Chlorobiphenyl isomers with chlorine substitutions in both the 4- and 4'- positions tend to be biologically active and well retained in tissues. In addition to the inhibition of tumor induction by some chemicals, PCBs were also shown to inhibit the growth of experimental tumors in rats. Sprague-Dawley rats were innoculated with Walker 256 carcinosarcoma cells and the effects of PCBs determined. Both dietary and injected aroclor 1254 reduced the size of solid tumors and increased animal life span. The time course of induction and inhibition of several enzymes in the liver of male C57BL/6 and ddy mice fed a diet containing Kanechlor-500 (500 ppm) was examined. Controls were maintained without treatment. Four animals/group were killed at 1, 2, 3, 6, and 10 weeks, following a 24 hr fast. In treated C57BL/6 and ddY mice there was an increase in the microsomal p450 level at 1 week. In treated C57BL/6 mice, the activity of mitochondrial delta-aminolevulinic acid synthetase (ALA-S) gradually increased for 2 wk (5.7 times the control value) and then rose rapidly for 3 wk (20 times the control value). These changes were accompanied by the rapid development of porphyria (characterized by increased excretion and hepatic accumulation of uroporphyrin). The activity of uroporphyrinogen decarboxylase (URO-D) was depressed approximately 40% within the first wk and 80% within 3 wk. In treated ddY mice there was a moderate increase of ALA-S (8 times the control at 3 wk); URO-D activity was unaffected for 3 wk and a significant decrease (p value not given) was observed at wk 6. Activities of ALA-S and URO-D in both strains of control mice were constant during the study. The control level (time 0) of URO-D in ddY mice was significantly higher (p< 0.01) than that of C57BL/6 mice, whereas control ALA-S activities were similar in the 2 strains. In C57BL/6 mice, the hepatic uroporphyrin level was elevated during the first week of exposure. By the third week, the liver porphyrin level was 2100 times that of the controls. Porphyrin did not accumulate in treated ddy mice at week 3, was slightly increased at week 6, and remained constant at week 10. There were no increases in uroporphyrin levels in untreated mice. /Kanechlor-500/ Groups of eight female Sprague-Dawley rats were fed 50 ppm Aroclor 1242 or Aroclor 1254 in their normal diets for seven months. One group of animals served as controls. Because (86)Rb mimics K+ in membrane transport, it was used to assess the amount of K+ uptake in erythroid cells. In a culture medium depleted of K+, the uptake of (86)Rb by erythroid cells was significantly lower in the Aroclor 1254-treated group (7.78%) (p< 0.05) compared with the control group (21.9%). Uptake of (86)Rb in the Aroclor 1242-treated group was not significantly lower than that of controls. In a sodium-depleted culture medium, erythroid cells from only the Aroclor 1254-treated animals showed a minimal, but significant reduction in (86)Rb uptake (1.16%) (p< 0.05) compared with the control group (3.91%). The difference in 86(Rb) uptake between the Na+ and K+-depleted culture media was attributed to the relative saturation of the K+ transport system. When erythroi cells were challenged with ouabain in order to suppress Na+, K+, and ATPase activity, (86)Rb uptake was depressed in all but the Aroclor 1254 group (this group had already been maximally depressed). Juvenile rainbow trout (Salmo gairdneri) were fed diets of coho salmon containing polychlorinated biphenyls (PCBs) naturally bioaccumulated from Lake Michigan, Lake Ontario, or the Pacific Ocean for a 20 wk period. Gas chromatographic analysis indicated that the bioaccumulated PCB levels in rainbow trout were similar to the levels in coho salmon used as dietary supplements. Following dietary exposure to control chow or coho salmon from the Pacific Ocean, the rainbow trout contained low PCB levels, whereas trout which were fed Lake Michigan salmon and Lake Ontario salmon contained logarithmically elevated levels of PCBs. The effect on natural resistance was assessed by challenge with a titrated dose of Vibrio anguillarum (VA-58). The ability to mount a protective immune response in trout exposed for a 20-wk period to control or Lake Ontario coho salmon diets was determined by immunization with a VA-58 bacteria followed by challenge with virulent VA-58. A high level of protective immunity was demonstrated in all dietary groups suggesting that the parameters of host resistance of rainbow trout were not compromised following dietary exposure to Great Lakes coho salmon. Eggs of three seabird species, double-crested cormorant (Phalacrocorax auritus), Leach's storm-petrel (Oceanodroma leucorhoa), and Atlantic puffin (Fratercula artica) were collected at 4-yr intervals from 1968 to 1984, from colonies (4 to 10 eggs/colony) in eastern Canada (A: Great Island, Newfoundland; B: Kent Island C: Manawagonish Island and D: Machias Seal Island, Bay of Fundy; and E: Ile-aux-Pommes, St. Lawrence River) and analyzed for organochlorines. PCBs declined significantly in all species from the Bay of Fundy, and from site A, but not significantly at site E. Over the entire period, PCB residues were highest in the cormorant. Channel catfish were obtained from Devil's Swamp (exposed fish), a river basin in southern LA heavily impacted by industrial complexes and hazardous waste sites. Reference fish were taken from LA State University's experimental Ben Hur aquaculture facility. The hepatic microsomal mediated O-dealkylation of various substituted alkoxyresorufins by the catfish were compared and correlated with polychlorinated biphenyl (PCB) contents from fat tissues of these fish. The most abundant PCB congeners found were pentachlorinated PCB (3900 ppb) followed by hexachlorinated (2800 ppb), tetrachlorinated (2400 ppb), heptachlorinated (540 ppb), octachlorinated (230 ppb), trichlorinated (130 ppb) and dichlorinated (40 ppb) biphenyls. The monochlorinated, nonochlorinated and decachlorinated biphenyls were represented in trace concn. Fatty tissue from reference fish were essentially devoid of PCB congeners. Specific activities and turnover numbers of 7-methoxyresorufin, 7-ethoxyresorufin, 7-pentoxyresorufin and benzyloxyresorufin O-dealkylases in Devil's Swamp microsomes of both male and female fish were significantly elevated relative to that of reference fish. When expressed per mg of protein, the degree of induction of these activities was notably higher in female catfish than in male catfish. To study the chronic effects of contaminated sediments on mortality, growth, gonad production and bioaccumulation in the urchin, Lytechinus pictus, urchins were exposed to 3 of the most contaminated sediment types in southern California and to a control sediment in the laboratory for 60 days in flow through experiments. Initial concentrations of polychlorinated biphenyls in the sediments used were very high (1118-3484 ng/g vs < 59 ng/g dry wt in the control), as were those of other contaminants. The sediments caused significant mortality and reduction of growth. Both male and female gonad production was also significantly decreased. Gonads accumulated up to 7.4 ppm polychlorinated biphenyls during the 60 day exposure period, but their concentrations of Cd, Cu and Zn were greatly reduced. In order to investigate interspecific responses to pollutants, physiological and biochemical parameters were studied in 2 sp of Gobiidae under both natural and experimental conditions. In addition to higher mixed function oxidase activity, Gobius niger, collected in a heavily polluted port, had higher polychlorinated biphenyls residues (0.45 ug/g dry wt vs 0.23 ug/g dry wt) than another sp, Zosterisessor ophiocephalus, collected from a relatively clean lagoon. After 20 days of acclimatization to clean water, the 2 sp exhibited practically identical levels of mixed function oxidase activity and polychlorinated biphenyls residues. Subsequent exposure to polychlorinated biphenyls (Arochlor 1260) at 10 ug/l resulted in considerably higher mixed function oxidase activity in G niger than in Z ophiocephalus and the polychlorinated biphenyls residue level was 4 times higher in G niger than in Z ophiocephalus after 20 days of exposure. Two groups of 12 female common seals (Phoca vitulina) were fed fish having high levels of polychlorinated biphenyl (PCB) contamination from the Wadden Sea (Group 1), or fish having low PCB contamination from the northeast Atlantic (Group 2) for almost 2 yr. Seals in Group 1 had a drastic reduction in plasma retinol concn as compared to those in Group 2 (30 to 55% reduction). The PCB-induced reduction in plasma retinol levels disappeared when seals were subsequently fed low-PCB Atlantic Ocean fish for 6 mo. Significant reductions of total and free thyroxine and triiodothyronine were also observed in Group 1. Regeneration experiments on the liver of flounder (Platichthys flesus L.) were performed to identify the role of diverse pollutants (chlorinated hydrocarbons including polychlorinated biphenyls) in the pathogenesis of the liver abnormalities observed during a 3-yr multidisciplinary survey in the Elbe estuary (Federal Republic of Germany). Flounder kept under contaminant-free conditions and fed ad libitum with uncontaminated food indicated initial and complete liver regeneration in 50% of the individuals after 20 days, and in 70% after 40 days. Signs of regeneration, diagnosed at the light and electron microscope level were accompanied by a significant decr in the concn of chlorinated hydrocarbons in the liver. Livers of flounder without regenerative signs maintained their high levels of contaminants. The ultrastructural findings indicated that transfer of Elbe flounder into a contaminant-free environment induced incr activity of biotransformation and detoxification in the hepatocytes (tubular smooth endoplasmic reticulum, lysosomes). Rhesus monkeys exposed to polychlorinated biphenyl mixtures during gestation and lactation were tested on two-choice discrimination-reversal learning (DR). In the first experiment, offspring of mothers fed 1.0 ppm Aroclor 1248 (avg exposure 20.7 + or - 3.1 mo), and offspring born 1.5 yr after maternal exposure to 2.5 ppm Aroclor 1248 ended (avg exposure 18.2 + or - 1.7 mo) did not differ from controls on spatial, color or shape discrimination-reversal problems. In the second experiment, offspring of mothers fed 0.25 or 1.0 ppm Aroclor 1016 (avg exposure of 21.8 + or - 2.2 mo) and offspring born 3 yr after maternal exposure to 2.5 ppm Aroclor 1248 ended were tested on the same spatial, color and shape problems, but a spatial problem with color and shape as irrelevant cues was inserted after the initial spatial problem. Performance of the high dose Aroclor 1016 offspring was impaired on the initial spatial problem, and facilitated on the shape problem. Performance of the Aroclor 1248 postexposure offspring was facilitated on the shape problem. Different combinations of 2,5,2',5'- and 3,4,3',4'-polychlorinated biphenyls and Aroclor 1254 were applied to human lymphocyte cultures, which were subsequently examined for chromosome breakage, rearrangements, sister-chromatid exchange, and mitotic delay. Results were compared to similar cultures treated with the known mutagen cyclophosphamide. In one experiment, parallel cultures were exposed to a final culture concn of either 10-4, 10-3, 10-2, or 10-1 ug/ml of 3,4,3',4' or to a 1.0 ug/ml dose of 2,4,2',5' and to either 10-3 ug/ml or 10-5 ug/ml of cyclophosphamide or to 25, 20, 10 or 5 ng/ml mitomycin C. Cells were also exposed to combinations of 2,5,2',5'- and 3,4,3',4'-polychlorinated biphenyl using either a combination of 1 ug/ml 2,5,2'5'- with 10-2, 10-3, 10-4 or 10-5 ug/ml 3,4,3',4'-polychlorinated biphenyl or a combination of 10-5 ug/ml 3,4,3'4'-polychlorinated biphenyl with 10-1, 10-2, or 10-3 ug/ml 2,5,2'5'-polychlorinated biphenyl. In other experiments, parallel cultures were treated with either 1 ug/ml or 10-1 ug/ml 2,4,5,2',4',5'-polychlorinated biphenyl as well as to a combination of 10-5 ug/ml 3,4,3',4' and 10-1 ug/ml 2,4,5,2',4',5'-polychlorinated biphenyl. In addition, either Aroclor 1254 or a fish extract containing Aroclor 1254 was added to parallel cultures at 1.1 ug/ml, 1.1X10-1 ug/ml or 1.1X10-2 mg/ml. Results showed that one planar polychlorinated biphenyl congener, 3,4,3',4'-tetrachlorobiphenyl, caused dose-related chromosome breakage in human lymphocytes exposed in vitro to 0.1-10-4 ug/ml. In contrast, the non-planar 2,5,2'5'- polychlorinated biphenyl, did not cause chromosome damage in comparable tests even at concn as high as 1 ug/ml. When the 3,4,3',4' congener at a concn lower than that which causes chromosome breakage (10-5 ug/ml) was combined with a non-clastogenic concn of the 2,5,2'5' congener, the chromosomal damage observed was far in excess of what one would expect from higher doses of the 3,4,3',4' congener alone. Compound ... Polychlorinated biphenyls. Species/Target Organ ...Rat, mouse/liver. /From table/ Xenobiotics that induce liver microsomal enzymes and disrupt thyroid function in rats include ... polyhalogenated biphenyls (PCB, PBB) ... . ... In certain strains of mice these compounds alter liver cell turnover and promote the development of hepatic tumors from spontaneously initiated hepatocytes. As pesticide use continued, however, reports of wildlife mortalities and declining avain populations spawned concern among biologists in several countries. Studies demonstrated residues of ... polychlorinated biphenyls (PCBs) All have ... effects in experimental animals: increased rate of neoplasms (particularly of the liver), induction of drug-metabolizing enzymes, anemia, weight loss, liver necrosis, immune changes with thymic and splenic atrophy, skin lesions, changes in serum lipids, estrogen effects, neurobehavioral changes, and reproductive dysfunction. /Dioxin, polychlorinated biphenyls, and dibenzofurans/ A treatment-related decrease in androgen-stimulated erythrocyte production is observed in male rats after a single intraperitoneal injection of relatively high levels of PCBs, suggesting a decrease in circulating androgen. Deleterious effects on spermatogenesis in rodents and fish occur after oral administration of PCB. Administration of PCB also lowers fertility in mice, rats, and monkeys. PCBs administered to neonatal rats exerted longlasting effects on hepatic function, resulting in altered circulating levels of gonadal hormones. These data suggest that prenatal exposure to PCBs may result in compromised fertility later in life as a result of altered function not only in the genital organ system but also in extragenital organs (e.g., liver). Although animal studies have proven the carcinogenicity of PCBs, there is no conclusive evidence that exposure to PCBs results in an increased incidence of cancer in humans. Animal studies have supported the immunotoxicity of PCBs ...
TSCA Test Submissions: This study evaluated the potential toxicity of polychlorinated biphenyl using the rabbit biological activity (RBA) test. Male New Zealand albino rabbits (4) received daily dermal applications of 50 mg polychlorinated biphenyl/kg/day for 20 consecutive days. An additional group of 8 male rabbits received no treatment and served as controls. The animals were weighed prior to study initiation and on days 7, 14, 21, and 28 and observed periodically for mortality and skin reactions. The animals were sacrificed on day 20, necropsied and examined histopathologically. The testes were weighed at necropsy and testes to body weights were calculated. Mortality (2 of 4 animals died on days 6 and 13, respectively, and were replaced) and behaviorial changes were reported. All animals exhibited inactivity, anorexia, muscle weakness, and moderate to severe weight loss. Skin irritation included moderate to severe erythema and edema followed by dryness, cracking, and scarring. Moderate changes of spermatogenic depression with occasional bizarre forms was reported in 2/4 animals. No further irritation or histopathological alterations were reported.
Metabolism/Pharmacokinetics:
Metabolism/Metabolites: THE DEGRADATION & ELIMINATION OF PCB CONGENERS APPEAR TO TAKE PLACE VIA HEPATIC MICROSOMAL ENZYME SYSTEM. TWO POSSIBLE MECHANISMS FOR BIOTRANSFORMATION HAVE BEEN SUGGESTED ... THE FIRST & MOST RAPID ... INVOLVES FORMATION OF AN ARENE OXIDE INTERMEDIATE ... THE SECOND & MUCH SLOWER USES A DIFFERENT HYDROXYLATION SYSTEM ... PCBs are ... poorly metabolized and can accumulate in human and animal tissues. PCBs alter the hepatic metabolism or gonadal hormones, and, therefore, have the potential to alter the reproductive characteristics of the affected individual. There appears to be little metabolism of PCBs with 6 or more chlorine substituents ... . ...The parent compound is also eliminated in various quantities in feces, hair, and maternal milk, but very little unmetabolized compound is excreted in the urine. ... As the rate of chlorination increases on both phenyl rings, the rate of metabolism decreases ... Phenolic products are the major PCB metabolites, though sulfur-containing metabolites, trans-dihydrodiols, polyhydroxylated PCBs, and methyl ether derivatives have also been identified. Consistent with the histopathological observation of fatty degeneration in the liver ..., short term exposure to commercial mixtures of PCBs induced increases in the contents and concentrations of total lipids, triglycerides, cholesterol, and/or phospilipids in this organ of the rat and rabbit ... . Many PCBs are metabolized to methylthio derivatives in mice, seals, and humans. The metabolic pathways leading to the generation of these metabolites have been shown to involve glutathione conjunction of an arenoxide intermediate ... . Rates of PCB metabolism vary greatly with species and with the degree and positions of chlorination.
Absorption, Distribution & Excretion: DURING MARCH 1964 AND FEBRUARY 1970, 48 OF 169 GOLDEN EAGLES FROM 22 STATES WERE FOUND TO CONTAIN PCBS IN EITHER BRAIN, HEART, KIDNEY, LIVER, MUSCLE, OR FAT, IN CONCN RANGING FROM LESS THAN 1 TO 19 UG/G ON A WET BASIS. /IN 1970/ ... THE MEAN PCB LEVEL IN HUMAN MILK IN TWO CALIFORNIA CITIES WAS ABOUT 0.06 UG/ML OF WHOLE MILK. ... ANALYSIS OF LIPID FRACTION OF 80 SAMPLES OF HUMAN MILK FROM VARIOUS AREAS OF THE USA SHOWED THAT ALL EXCEPT 2 HAD CONCN ... FROM 0.4-10.6 UG/G. THE AVERAGE CONCN IN ALL SAMPLES WAS APPROX 1.7 UG/G. FORTY-THREE PERCENT OF 723 PLASMA SAMPLES FROM PERSONS IN SOUTH CAROLINA NOT OCCUPATIONALLY EXPOSED TO PESTICIDES WERE FOUND TO CONTAIN PCBS, WITH A MAXIMUM OF 0.029 UG/ML. Polychlorinated biphenyls are stored in body fat and not readily excreted except in breast milk and possibly through the placenta. Polychlorinated biphenyls (PCBs) are readily absorbed through the gut, respiratory system and skin. /PCBs/ may initially concentrate in the liver, blood, and muscle mass, but long-term storage in mammals is primarily in adipose tissue and skin. ... PCBs which are readily metabolized are also rapidly excreted in the urine and bile. Excretion in urine is most prominent for the least chlorinated, while bile becomes the more significant route of excretion for more highly chlorinated isomers. Those isomers which are most refractory to metabolism accumulate for increasing periods of time in fatty tissues. Highly chlorinated isomers are accumulated almost indefinitely. Animal studies have shown that PCB's can cross the placental barrier and are excreted in the mother's milk. In a plant in the United States the PCB plasma levels of workers assembling capacitors and transformers ranged from 10.0-2500 ppb. The plasma concentration increased with the intensity and duration of exposure. Polychlorinated biphenyl (PCB) concentrations in the blood of mothers who were occupationally exposed to PCBs in the capacitor manufacturing facility, and their children, were analyzed from 1975 to 1979. The factory terminated PCB use in 1972, and environmental PCBs were eliminated artificially. Despite this, blood PCB levels of the mothers were very high, ie, 10-100 times higher than that of non-occupationally exposed persons. ... By a present investigation which continued during a 5 yr period, the PCB levels in blood of children were influenced greatly by the duration of breast-feeding, but showed little relationship to the PCB levels in maternal blood. The PCB exposure period of the mothers, time of birth, and age of the children were less clearly related to the PCB levels in the children. The PCB concentration in the children's blood decreased at a constant rate and was independent of their blood PCB levels. A similar result was noted for their mothers' PCB levels. A slight difference, however, was found in the rate of decrease of blood PCB levels between the mothers and children. The results of questionnaire research on the health conditions and the medical examinations for the children showed that frequency of complaints, eg, red eye, fever, itchy skin, and carious teeth, related favorably to the duration of breast-feeding. Less severe findings, ie, decay of nails, pigmentation, mottled enamel, carious teeth, which were typical symptoms in Yusho patients, were observed in some children. ... Mayflies (Hexagenia limbata) collected from May to Nov 1986 from Lake St. Clair at temperatures of 10 to 20 deg C were exposed in 200 ml test chambers to a polychlorinated biphenyl, (14)C-2,4,5,2',4',5'-hexachlorobiphenyl, in flow-through water and sediment exposure tests. In the water exposure tests where the animals were in artificial burrows of stainless steel screen, the infusion rate was 100 ml/hr of dosed water, with no sediment present. Animals were removed after 1, 2, 4, and 6 hr exposure for radioanalysis. Animals remaining in the exposure chamber after the uptake phase were removed and placed in uncontaminated sediment for elimination for studies for 1, 3, 5, 7, and 14 days. The accumulation from sediment was measured by sorbing the radiolabeled compounds onto sediment in an aqueous slurry overnight. Exposed organisms were removed from the sediment at approximately 1, 3, 5, 7, and 14 days and were radioanalyzed by scintillation counting. The seasonal uptake and elimination rate constants for H limbata, respectively, were: 47.5 + or - 23.9 ml/g/hr and 0.007 + or - 0.001/ hr in May (10 deg C); 44.2 + or - 8.0 ml/g/hr and 0.005 + or - 0.002/hr in Jun (15 deg C); 40.8 + or - 37.3 ml/g/hr and 0.005 + or - 0.001/hr in Jul (15 deg C); 40.8 + or - 37.3 ml/g/hr and 0.007 + or - 0.001/hr in Aug (20 deg C); 128.7 + or - 20.3 ml/g/hr and 0.015 + or - 0.003/hr in Sept (20 deg C); 95.0 + or - 17.3 ml/g/hr and 0.017 + or - 0.002/hr in Sept 30 (20 deg C); and 45.5 + or - 16.1 ml/g/hr and 0004 + or - 0.0006/hr in Nov (10 deg C). Reported values for seasonal uptake rate constants have been corrected for sorption to dissolved organic carbon. Seasonal uptake clearance rate constants from sediment for H limbata for Jun and Aug, respectively, were: 0.030 + or - 0.01/hr (15 deg C) and 0.015 + or - 0.003/hr (20 deg C). The uptake of polychlorinated biphenyl (PCB) congeners was investigated in leaf composites and final fruits of four crop species at two alluvial mud sites (a control plot in the flood plain of the Normanskill, NY, and an experimental plot on Patroon Island, Albany, NY). Soy beans and corn were grown in the control plot. Soy beans, string beans, and pinto beans were grown in the experimental plot along with corn transplanted with soil confined in plastic bags from the control site. The three major constituents in each plant species were the same (2-mono-, 2,4'-di-, and 2,2'-dichlorobiphenyls), but thereafter the rank of the remaining major congeners varied according to species. Mean total PCB concentrations in leaves in ppb were 12-14 at the control site and 12-15 at the experimental site. However, samplings in late August showed relatively high levels of 30-50 ppb. Corn plants, tended to depurate PCBs over time. No trends for pinto beans or string beans were discernible. PCB levels (ppb) in fruits were as follows: corn kernels, 0.13 at both sites; corn husk, 3.06 at control site and 8.03 at experimental site; corn silk, 4.76 at control site; soybean beans, 0.55 at experimental site; soybean pods, 7.4 at experimental site. PCBs are well absorbed via the gastrointestinal tract, skin, and lungs but are poorly metabolized ... . Polychlorinated biphenyl (PCB) compounds are absorbed through inhalation and ingestion and also through the skin. They are carried in blood associated with serum lipdids. Highly chlorinated PCBs have a tendency to accumlate in body fat and the liver. Many organic compounds in the environment are highly lipophilic. This characteristic permits rapid penetration of cell membranes and uptake by tissues. Therefore, it is not surprising that highly lipophilic toxicants are distributed and concentrated in body fat. Such accumulation in adipose tissue has been demonstrated for ... polychlorinated ... biphenyls. Compounds such as polychlorinated ... biphenyls ... are knownto occur in milk, and milk can be a major route of their excretion. PCBs are stable, fat-soluble substances that are poorly excreted from the body. Fetuses and neonates are potentially more sensitive to PCBs than adults because of transplacental distribution and physiological differences. They lack the hepatic microsomal enzyme systems that facilitate metabolism and excretion of PCBs. ...The absorption and distribution of PCBs will ... take place via the lymphatic system (by the chylomicrones). Following absorption, the clearance of PCBs from the blood and tissues follows a biphasic pattern. The compounds rapidly clear from the blood and accumulate in the liver and adipose tissue or are metabolized in the liver to metabolites that are excreted in the urine and/or bile. ...PCBs are readily absorbed from the gastrointestinal tract following oral administration. ... PCBs within a human fetus are not evenly distributed. ... The highest level was found in the skin ... because of the high solubility of the compounds in adipose tissue. ...PCBs accumulate increasingly as the body fat of a fetus increases. ... Low residue levels in the brain were ... because PCBs have a poor affinity for the brain lipids. The ratio profiles of PCB levels in blood/adipose tissue, remained relatively static between the second and twentyseventh month of feeding. The data ... suggest that the bioaccumulation or retention of PCBs may be dose-dependent, particularly for adipose tissue. The excretion of PCBs is ... dependent on the metabolism of PCBs to form more polar compounds. ...The elimination of PCBs from all tissues will be dependent on the structure-dependent metabolism rates of the individual PCB congeners. PCBs can be excreted unmetabolized into the gastrointestinal tract.
Biological Half-Life: The bioaccumulation potential of three toxic coplanar polychlorinated biphenyl (PCB) isomers was investigated using green-lipped mussels (Perna viridis L) as a bioindicator, by transplanting 500 individuals from a relatively uncontaminated area to the heavily polluted Hang Hau, Junk Bay, Hong Kong. The compounds were 3,3',4,4'-tetrachlorobiphenyl, 3,3',4,4',5,-pentachlorobiphenyl, and 3,3',4,4',5,5'-hexachlorobiphenyl. Samples were collected at 0, 1, 2, 4, 6, 8, 10, 12, 14, 16, and 17 days. At 17 days, remaining mussels were back-transplanted to the original cleaner waters and further sampled during the depuration period at 0, 3, 6, 14, and 32 days. Highest levels of each PCB isomer was found on days 0 or 3 of the back-transplantation period. Maximum wet weight value for total PCBs was 630 ng/g. Maximum lipid weight value for total PCBs was 45,000 ng/g. Control mussels from the clean water contained 200 to 230 ng/g total PCBs; from the polluted water, 28,000 to 35,000 ng/g total PCBs. PCB levels at the end of the 32-day depuration period were higher than pre-exposure levels.
Mechanism of Action: Environmental chemical exposure associated with reproductive function /in females/ ... polychlorinated biphenyls (PCBs). ... Polychlorinated biphenyls (PCBs) are uterotropic. PCBS ARE WIDELY USED AS ENZYME INDUCERS IN RESEARCH LABORATORIES THROUGHOUT THE WORLD. THERE ARE INDICATIONS THAT CHLORINE CONTENT OF PCB MIXTURES IS RELATED TO LEVEL OF INCR ENZYMATIC ACTIVITY: MIXTURES CONTAINING LOWER PERCENTAGE OF CHLORINES WERE LESS ACTIVE THAN THOSE CONTAINING HIGHER PERCENTAGE. PRETREATMENT OF RATS WITH A SINGLE IP DOSE OF POLYCHLORINATED BIPHENYLS (0.33-3.33 MMOL/KG) PRODUCED A LONG-LASTING INCREASE IN THE IN VITRO ACTIVITY OF RAT LIVER MICROSOMAL UDP-GLUCURONYLTRANSFERASE TOWARDS P-NITROPHENOL & 4-METHYLUMBELLIFERONE BY CAUSING ENZYME INDUCTION. Different combinations of 2,5,2',5'- and 3,4,3',4'-polychlorinated biphenyls and Aroclor 1254 were applied to human lymphocyte cultures, which were subsequently examined for chromosome breakage, rearrangements, sister-chromatid exchange, and mitotic delay. Results were compared to similar cultures treated with the known mutagen cyclophosphamide. In one experiment, parallel cultures were exposed to a final culture concn of either 10-4, 10-3, 10-2, or 10-1 ug/ml of 3,4,3',4' or to a 1.0 ug/ml dose of 2,4,2',5' and to either 10-3 ug/ml or 10-5 ug/ml of cyclophosphamide or to 25, 20, 10 or 5 ng/ml mitomycin C. Cells were also exposed to combinations of 2,5,2',5'- and 3,4,3',4'-polychlorinated biphenyl using either a combination of 1 ug/ml 2,5,2'5'- with 10-2, 10-3, 10-4 or 10-5 ug/ml 3,4,3',4'-polychlorinated biphenyl or a combination of 10-5 ug/ml 3,4,3'4'-polychlorinated biphenyl with 10-1, 10-2, or 10-3 ug/ml 2,5,2'5'-polychlorinated biphenyl. In other experiments, parallel cultures were treated with either 1 ug/ml or 10-1 ug/ml 2,4,5,2',4',5'-polychlorinated biphenyl as well as to a combination of 10-5 ug/ml 3,4,3',4' and 10-1 ug/ml 2,4,5,2',4',5'-polychlorinated biphenyl. In addition, either Aroclor 1254 or a fish extract containing Aroclor 1254 was added to parallel cultures at 1.1 ug/ml, 1.1X10-1 ug/ml or 1.1X10-2 mg/ml. Results showed that one planar polychlorinated biphenyl congener, 3,4,3',4'-tetrachlorobiphenyl, caused dose-related chromosome breakage in human lymphocytes exposed in vitro to 0.1-10-4 ug/ml. In contrast, the non-planar 2,5,2'5'- polychlorinated biphenyl, did not cause chromosome damage in comparable tests even at concn as high as 1 ug/ml. When the 3,4,3',4' congener at a concn lower than that which causes chromosome breakage (10-5 ug/ml) was combined with a non-clastogenic concn of the 2,5,2'5' congener, the chromosomal damage observed was far in excess of what one would expect from higher doses of the 3,4,3',4' congener alone. The relative potencies of the commercial polychlorinated biphenyl (PCB) mixtures Aroclors 1260, 1254, 1248, 1242, 1016 and 1232 to inhibit the murine splenic plaque-forming cell response to sheep red blood cells was determined by dose-response ip treatment of C57BL/6 mice followed by logit plot analysis of the data. The ED50 values obtained for Aroclors 1260, 1254, 1248, 1242, 1016 and 1232 were 104, 118, 190, 391, 408, and 464 mg/kg or 0.28, 0.35, 0.66, 1.5, 1.5 and 2.0 mM/kg, respectively. The higher chlorinated PCB preparations (Aroclors 1260, 1254 and 1248) were more potent than the lower chlorinated preparations (Aroclors 1242, 1016 and 1232). Previous studies have shown that the interaction of a subeffective dose of Aroclor 1254 (25 mg/kg) with an immunotoxic dose (3.7 nM/kg) of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) resulted in significant antagonism of the toxicity of the latter compound. Co-treatment of mice with a 25 mg/kg dose of all the commercial Aroclors and with a 50 mg/kg dose of a reconstituted PCB mixture (resembling a PCB extract from human milk) with TCDD (3.7 nM/kg) showed that, with the exception of Aroclor 1232, all of the commercial PCBs and the reconstituted PCB mixture significantly antagonized the dioxin-mediated inhibition of the splenic plaque-forming cell response in C57BL/6 mice. Less chlorinated compounds are also subject to biotransformation, which may compromise dechlorination, oxidation, and conjugation phases. /Polychlorinated biphenyls/ The toxcity of some of the more active PCB ... isomers has been related to their ability to bind to a specific receptor protein, the Ah receptor, with subsequent translocation to the nucleus and induction of activation of several genes. Examples of indirect acting toxins include ... pesticides which interact with estrogen receptors ... or alter the rate of steroid production or clearance (e.g., PCBs) ... The underlying cause of the reproductive toxicity of PCBs, ... may be alterations in hormonal receptor binding and/or alterations in the steroid hormone balence through effects on metabolism and excretion.
Interactions: The toxicity of PCB is potentiated by carbon tetrachloride. Hepatocarcinogenesis initiated by 3'-methyl-4-dimethyl-azobenzene (3'-Me-DAB) in female Donryu strain rats was promoted by oral administration of polychlorinated biphenyls (PCBs) following initiation. Tumor incidences in animals treated with 3'-Me-DAB + PCB, 3'-Me-DAB alone, or PCB alone were 64%, 13% and 0%, respectively. PCB treatment preceding or simultaneous with 3'-Me-DAB treatment did not produce tumors. The relative potencies of the commercial polychlorinated biphenyl (PCB) mixtures Aroclors 1260, 1254, 1248, 1242, 1016 and 1232 to inhibit the murine splenic plaque-forming cell response to sheep red blood cells was determined by dose-response ip treatment of C57BL/6 mice followed by logit plot analysis of the data. The ED50 values obtained for Aroclors 1260, 1254, 1248, 1242, 1016 and 1232 were 104, 118, 190, 391, 408, and 464 mg/kg or 0.28, 0.35, 0.66, 1.5, 1.5 and 2.0 mM/kg, respectively. The higher chlorinated PCB preparations (Aroclors 1260, 1254 and 1248) were more potent than the lower chlorinated preparations (Aroclors 1242, 1016 and 1232). Previous studies have shown that the interaction of a subeffective dose of Aroclor 1254 (25 mg/kg) with an immunotoxic dose (3.7 nM/kg) of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) resulted in significant antagonism of the toxicity of the latter compound. Co-treatment of mice with a 25 mg/kg dose of all the commercial Aroclors and with a 50 mg/kg dose of a reconstituted PCB mixture (resembling a PCB extract from human milk) with TCDD (3.7 nM/kg) showed that, with the exception of Aroclor 1232, all of the commercial PCBs and the reconstituted PCB mixture significantly antagonized the dioxin-mediated inhibition of the splenic plaque-forming cell response in C57BL/6 mice.
Pharmacology:
Drug Warnings: Food and Environmental Agents: Reported Sign or Symptom in Infant or Effect on Lactation: Polychlorinated biphenyls and polybrominated biphenyls: Lack of endurance, hypotonia, sullen, expressionless faces. /From Table 7/
Interactions: The toxicity of PCB is potentiated by carbon tetrachloride. Hepatocarcinogenesis initiated by 3'-methyl-4-dimethyl-azobenzene (3'-Me-DAB) in female Donryu strain rats was promoted by oral administration of polychlorinated biphenyls (PCBs) following initiation. Tumor incidences in animals treated with 3'-Me-DAB + PCB, 3'-Me-DAB alone, or PCB alone were 64%, 13% and 0%, respectively. PCB treatment preceding or simultaneous with 3'-Me-DAB treatment did not produce tumors. The relative potencies of the commercial polychlorinated biphenyl (PCB) mixtures Aroclors 1260, 1254, 1248, 1242, 1016 and 1232 to inhibit the murine splenic plaque-forming cell response to sheep red blood cells was determined by dose-response ip treatment of C57BL/6 mice followed by logit plot analysis of the data. The ED50 values obtained for Aroclors 1260, 1254, 1248, 1242, 1016 and 1232 were 104, 118, 190, 391, 408, and 464 mg/kg or 0.28, 0.35, 0.66, 1.5, 1.5 and 2.0 mM/kg, respectively. The higher chlorinated PCB preparations (Aroclors 1260, 1254 and 1248) were more potent than the lower chlorinated preparations (Aroclors 1242, 1016 and 1232). Previous studies have shown that the interaction of a subeffective dose of Aroclor 1254 (25 mg/kg) with an immunotoxic dose (3.7 nM/kg) of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) resulted in significant antagonism of the toxicity of the latter compound. Co-treatment of mice with a 25 mg/kg dose of all the commercial Aroclors and with a 50 mg/kg dose of a reconstituted PCB mixture (resembling a PCB extract from human milk) with TCDD (3.7 nM/kg) showed that, with the exception of Aroclor 1232, all of the commercial PCBs and the reconstituted PCB mixture significantly antagonized the dioxin-mediated inhibition of the splenic plaque-forming cell response in C57BL/6 mice.
Environmental Fate & Exposure:
Environmental Fate/Exposure Summary: Since October of 1977, PCBs have not been produced commercially in the United States. Current evidence suggests that the major source of PCB release to the environment is an environmental cycling process of PCBs previously introduced into the environment. This cycling process involves volatilization from ground surfaces (water, soil) into the atmosphere with subsequent removal from the atmosphere via wet/dry deposition and then revolatilization. PCBs are also currently released to the environment from landfills containing PCB waste materials and products, incineration of municipal refuse and sewage sludge, and improper (or illegal) disposal of PCB materials, such as waste transformer fluid, to open areas. PCBs can also be found in older transformers and capacitors still in use that have not been replaced with PCB-free dielectric fluid. PCBs are mixtures of different congeners of chlorinated biphenyl and the relative importance of the environmental fate mechanisms generally depends on the degree of chlorination. In general, the persistence of PCBs increases with an increase in the degree of chlorination. Mono-, di- and trichlorinated biphenyls (Aroclor 1221 and 1232) biodegrade relatively rapidly, tetrachlorinated biphenyls (Aroclors 1016, 1242 and 1248) biodegrade slowly, and higher chlorinated biphenyls (Aroclors 1254 and 1260) are resistant to biodegradation. Although biodegradation of higher chlorinated congeners may occur very slowly on an environmental basis, no other degradation mechanisms have been shown to be important in natural water and soil systems. If released to soil, PCBs adsorb strongly to soil particles with adsorption generally increasing with the degree of chlorination of the PCB. Log Koc values for the various congeners range from 4.0 for monochlorobiphenyl to 5.5 for nonachlorobiphenyl, estimated using a structure fragment constant method. PCBs will generally not leach significantly in aqueous soil systems; the higher chlorinated congeners will have a lower tendency to leach than the lower chlorinated congeners. In the presence of organic solvents PCBs may leach quite rapidly through soil. Vapor loss of PCBs from soil surfaces appears to be an important fate mechanism with the rate of volatilization decreasing with increasing chlorination. Because the lower chlorinated PCBs volatilize more readily from soil surfaces, the higher chlorinated species tend to concentrate in soil environments. Although the volatilization rate from soils may be low, the total loss by volatilization over time may be significant because of the persistence and stability of PCBs. It has been estimated that the fraction of total PCBs found in the atmosphere consists of only 0.05% of total global PCBs. If released to water, adsorption to sediment and suspended matter will be an important fate process; PCB concns in sediment and suspended matter have been shown to be greater than in the associated water column. Although adsorption can immobilize PCBs (especially the higher chlorinated congeners) for relatively long periods of time, eventual re-solution into the water column has been shown to occur. The PCB composition in the water will be enriched by lower chlorinated PCBs because of their greater water solubility while the higher chlorinated PCBs will remain adsorbed to sediment and suspended particles. Volatilization from water surfaces is expected to be an important fate process based upon PCBs estimated Henry's Law constant values ranging from 7.36X10-4 for monochlorobiphenyl to 1.8X10-8 atm-cu m/mole for octachlorobiphenyl. Estimated volatilization half-lives for a model river and model lake will range from 2.5 to 70 hrs and 6 to 39 days, respectively. However, volatiliza tion from water surfaces is expected to be attenuated by adsorption to suspended solids and sediment in the water column. Although the resulting volatilization rate may be low due to adsorption, the total loss by volatilization over time may be significant because of the persistence and stability of the PCBs. This leads to an atmospheric enrichment of low-molecular weight isomers in the atmosphere. PCBs have been shown to bioconcentrate significantly in aquatic organisms. Researchers studying the bioconcentration of PCBs in fish found that the log BCF ranged from 4.4 for 2-chlorobiphenyl to 6.2 for 2,2',4,4',5,5'-hexachlorobiphenyl. If released to the atmosphere, PCBs will exist in both the vapor-phase and particulate phase based on estimated vapor pressures ranging from 1.2X10-3 mm Hg for monochlorobiphenyl to 7.6X10-9 mm Hg for nonachlorobiphenyl. The dominant atmospheric transformation process for these congeners is the vapor-phase reaction with hydroxyl radicals which have estimated half-lives ranging from 4.6 to 490 days. Physical removal of PCBs from the atmosphere is accomplished by wet and dry deposition. This is expected to occur more rapidly than reaction with hydroxyl radical and will therefore be the dominant fate of PCBs in the atmosphere. Only a small portion of total PCBs are in the vapor phase at any one time. The concn of PCBs in the colder and more remote regions of the world consist primarily of those with higher mobility, lower chlorination and ortho-positioned chlorine atoms. Dermal exposure is important for workers involved with handling of PCB-containing electrical equipment, spills or waste-site materials. The major PCB exposure routes to the general public are through food and drinking water, and by inhalation of contaminated air. Exposure through consumption of contaminated fish may be especially important to the general public. (SRC)
Probable Routes of Human Exposure: ... Environmental contamination may be a significant source of human exposure. Likely routes of exposure for the general population are water and particularly food, while inhalation and dermal contact are likely to be more significant routes in occupational exposure. Serum samples from 285 4-yr-old Michigan children were evaluated for levels of 11 environmental contaminants. Polychlorinated biphenyls (PCBs) were found in half the samples tested. Nursing (mothers' milk) was the principal source of these exposures. Congener-specific analysis documented the presence of at least one highly toxic PCB congener, 2,3',4,4',5-pentachlorobiphenyl. Mothers were exposed to PCBs through their consumption of Lake Michigan sport fish or farm products (milk or meat) contaminated with PCBs as ascertained by the Michigan Department of Public Health. HUMAN EXPOSURE TO SMALL AMT OF PCB'S IS WIDESPREAD AS A RESULT OF ENVIRONMENTAL CONTAMINATION & HIGH STABILITY OF THESE CMPD. Toxic non-, mono- and di-ortho coplanar PCB congeners were determined in terrestrial mammals (human, cat and dog), a coastal marine mammal (finless porpoise), and marine mammals (Dall's porpoise, Baird's beaked whale, and the killer whale). Total PCBs were 1.0 ug/g (human), 2.0 (cat), 0.10 (dog), 320 (finless porpoise), 8.6 (Dall's porpoise), 2.3 (Baird's beaked whale), and 370 ug/g wet wt (killer whale). The concn of coplanar PCBs were found to be higher in the order of di-ortho > mono-ortho > non-ortho congeners and were significantly higher than the levels of toxic dioxins and furans. The geographical distribution of these chemicals based on the relative abundance of coplanar PCB congeners with reference to total PCBs did not vary in terrestrial, coastal and open ocean mammals, whereas that of polychlorinated dibenzofurans and polychlorinated dibenzodioxins apparently decr from land to ocean. 2,3,7,8-Tetrachlorodibenzo-p-dioxin toxic equivalent analysis revealed that higher aquatic predators such as cetaceans receive a greater toxic threat from 3,3',4,4',5- and 2,3,3',4,4'-pentachlorobiphenyls than polychlorinated dibenzofurans and polychlorinated dibenzodioxins. Dermal exposure is important for workers involved with handling PCB containing electrical equipment, spills or waste-site materials and for swimmers in polluted water(1). Exposure through consumption of contaminated fish may be especially important. Large exposure may be characteristic of PCB fires(1). It was estimated that approximately 12,000 USA workers were potentially exposed to PCBs annually from 1970-1976(1). A review of occupational exposure data found that workroom air of factories using PCBs for manufacturing may vary from 0.1 to 10.5 mg/cu m(2). Concentrations of PCBs in the air during different manufacturing processes are as follows: capacitor mfg (80-275 ug/cu m), electrical equipment mfg (0-264 ug/cu m), transformer inspection (0.4-9 ug/cu m)(3). Airborne concentrations in the room of overheated transformers containing PCBs were found to be 50-90 ug/cu m one day after the overheating occurred(4). NIOSH (NOES Survey 1981-1983) has statistically estimated that 459 workers, number of female workers unreported, were potentially exposed to PCBs in the US(1). Occupational exposure to PCBs may occur through inhalation and dermal contact with this compound at workplaces where PCBs are still present(such as hazardous waste sites)(SRC). The general population may be exposed to PCBs via ingestion of food(2), particularly fish(3-5), and drinking water(6-8) contaminated with PCBs(SRC). The potential levels of PCBs in indoor air may be from 2 to 10 times higher than typical levels found in outdoor air due in part to the presence of PCB-containing transformers and electrical parts(1).
Body Burden: /IN 1970/ ... THE MEAN PCB LEVEL IN HUMAN MILK IN TWO CALIFORNIA CITIES WAS ABOUT 0.06 UG/ML OF WHOLE MILK. ... ANALYSIS OF LIPID FRACTION OF 80 SAMPLES OF HUMAN MILK FROM VARIOUS AREAS OF US SHOWED THAT ALL EXCEPT 2 HAD CONCN ... FROM 0.4-10.6 UG/G. THE AVERAGE CONCN IN ALL SAMPLES WAS APPROX 1.7 UG/G. /POLYCHLORINATED BIPHENYLS/ FORTY-THREE PERCENT OF 723 PLASMA SAMPLES FROM PERSONS IN SOUTH CAROLINA NOT OCCUPATIONALLY EXPOSED TO PESTICIDES WERE FOUND TO CONTAIN PCBS, WITH A MAXIMUM OF 0.029 UG/ML. /POLYCHLORINATED BIPHENYLS/ PCB CONTAMINATION IS FOUND TO BE ALMOST UNIVERSAL, INCLUDING HUMAN MILK, HUMAN ADIPOSE TISSUE, & BRAIN & LIVER OF SMALL CHILDREN. Polychlorinated biphenyl blood residues were measured in 29 infertile males and in 14 matched control subjects at a hospital in Jerusalem, Israel. The patients' ages ranged from 25 to 45 years. The patients exhibited one or more impaired semen characteristics such as decreased spermatozoa count, lower sperm motility, or a greater proportion of morphologically abnormal spermatozoa. The control group, matched by age and smoking habits, consisted of randomly selected patients with minor illnesses. Each of them had at least one child not older than two years of age. None of the subjects had a history of occupational exposure to organochlorine compounds. The polychlorinated biphenyl levels were measured by GC-ECD. The mean concentration of total polychlorinated biphenyls in the infertile patients was 11.21 +/- 13.48 ng/g blood serum (range 0 to 64.2 ng/g). The control subjects had a mean concentration of 7.94 +/- 14.69 ng/g (range 0 to 47.3 ng/g). Mean PCB concns ranging from 0.35 to 8.3 mg/kg have been detected in human fat of subjects from 12 different nations, including the USA(1). PCB levels of 19-24 ug/kg and 57.2-74.2 mg/kg were found in milk and fatty tissue, respectively, of Norwegian women(2). Human adipose tissue of 46 Japanese males and 46 females was found to contain mean levels of 3.29 and 2.75 ppm PCB in 1981(3). Mean and median concn of 5 and 4 ppb, respectively, were detected in the blood of 738 new employees of a CA electric company; these values are comparable to previously published values for PCB concn in people without occupational exposure(4). Fifty samples of human milk from Finland were found to contain mean PCB levels of 0.016 and 0.45 mg/kg in whole milk fat, respectively(5). Analysis of serum specimens of 1462 Michigan residents in 1978 found mean PCB levels of 2-10 ppb(6). The burden of PCBs in human fat has been found to range between 500 and 1500 ppb(7). EPA human monitoring program found PCB body pattern to be similar irrespective of source for non-occupationally exposed humans; PCB pattern resembled Aroclor 1260(1). The 2,3,4,5-PCBs are preferentially enriched in human milk with a least 2 rings substituted (>Cl4). Thus the PCB congeners from Aroclor 1016 would not be major contributors (only for Aroclor 1016, 1221)(1).
Average Daily Intake: AIR INTAKE: (assume typical ambient air concn of 5 ng/cu m)= 100 ng; WATER INTAKE: Predominant source of PCB exposure in the adult male when drinking water levels exceed 1.0 ug/l(2). FOOD INTAKE: (assume 70 kg body wt)= 210-560 ng based on monitoring data for years 1980-1982(1). AIR INTAKE: (assume 0.02 ug PCB/m cu, 16 hrs indoors) - 0.05 ug/kg/day(1). WATER INTAKE: Predominant source of PCB exposure in the adult male when drinking water levels exceed 1.0 ug/l(1). FOOD INTAKE: 0.01 ug/kg/day(1).
Artificial Pollution Sources: Polychlorinated biphenyls have entered the environment ... from manufacturing plants, during destruction of manufactured articles containing PCBs in municipal and industrial waste-disposal burners, through gradual wear and weathering of PCB-containing products, and through leaching from land-fill dumps. Because polychlorinated biphenyls (PCBs) are not naturally occurring substances, their dissemination is entirely the result of human activity. Their entry into the environment has occurred by vaporization into the atmosphere, and by spilling or dumping into water or onto land. It has been estimated that of the l970 sales of PCBs in North America, only 20 percent represented a net incr in the total amount in service. Estimated sources of loss for that yr were l to 2x10+3 tons for evaporation; 4 to 5x10+3 tons for leaks and disposal of fluids; and 22x10+3 tons for disposal by incineration and burial. The cumulative input to the environment between 1930 and 1970 was estimated to be 3x10+4 tons in air, 6x10+4 tons to fresh and coastal waters, and 3x10+5 tons to dumps and landfills. In that time, up to one-third of the PCBs released to air and one-half of that released to water were probably degraded. In preparation of remedial action plans for the St. Clair, Detroit, and St. Mary's rivers, a planning-level methodology for evaluation of pollutant loadings from urban nonpoint sources was developed and applied in 3 Canadian cities: Sarnia, Sault Ste. Marie, and Windsor. This methodology uses computed annual volumes of runoff and mean constituent concn, estimated from field sampling, to produce estimates of annual pollutant loadings. The mean stormwater concn and point source equivalent concn (ug/l) for polychlorinated biphenyls (PCBs) were 0.179 and 0.179 for Sarnia, 0.0269 and 0 for Sault Ste. Marie, and 0.0888 and 0.641 for Windsor, respectively. Since October of 1977, PCBs have not been produced commercially in the United States(1). Current sources of PCB release to the environment include releases from landfills containing PCB waste materials and products, incineration of municipal refuse and sewage sludge, and improper (or illegal) disposal of PCB materials, such as waste transformer fluid, to open areas(2,3). PCBs can also be found in older transformers and capacitors still in use that have not been replaced with PCB-free dielectric fluid. Monitoring of atmospheric emissions of PCBs from landfills and incinerator stacks has indicated that emission rates from these sources are small compared to the 900,000 kg/yr of PCBs estimated to cycle through the atmosphere over the USA annually(3). Atmospheric washout and fallout have been identified as non-point sources of PCB exposure to the environment(2,4,5). Although additional research is required for a definitive answer, current evidence suggests that the major source of PCB release to the environment is an environmental cycling process of PCBs previously introduced into the environment. This cycling process involves volatilization from ground surfaces (water, soil) into the atmosphere with subsequent removal from the atmosphere via wet/dry deposition and then revolatilization(3,4,5,SRC). During all these cycles, the PCB composition changes in each phase relative to the original Aroclor so that specific Aroclor contributions may become impossible to assign. Specific congener PCB analysis must be performed on environmental media to obtain the total extent of PCB pollution(6).
Environmental Fate: The polychlorinated biphenyls (PCBs) in sediment and/or fish samples from at least 5 different locations show changes in gas chromatograph peak distribution indicative of reductive dechlorination. Several different dechlorination processes, each presumably mediated by a different population of anaerobic bacteria with its own distinctive pattern of PCB congener selectivity, appear to be operating. Six of these processes were characterized in detail as to the changes occurring in each of the individual PCB congeners or isomer groups detectable by capillary gas chromatography or gas chromatography-mass spectroscopy on a DB-1 column. The patterns of congener reactivity indicate that the observed transformation processes fall into 2 broad categories: ortho-, meta-, and para-dechlorinations. ... With relative reactivities determined mainly by molecular shape. Both types of dechlorination preferentially remove PCB congeners of toxicological concern, and both produce lower congeners that are biodegradable by environmental aerobes. ... Percentages of chlorine /in mixtures/ changes with time and location as the mixtures are transported through the environment. A model, based on the fugacity concept, is used to describe the time varying fate of polychlorinated biphenyls (PCBs) in Lake Ontario over the period 1940 to 2000. Expressions are included for loading and partitioning of PCBs between the phases of air, aerosols, water, suspended and bottom sediments, various trophic levels of aquatic organisms and gull eggs. Also included are expressions for transformation rates, and transport rates for diffusion between water and sediment, and water and air, wet and dry atmospheric deposition, sediment deposition, burial and resuspension, and water and suspended matter inflow and outflow. Results obtained by numerical integration and by assuming reasonable loading and air concn are in accord with reported data. The PCB concn rise steadily until about 1968 to 1972, reaching maxima of 4.0 ng/l in the water, 1,074 ng/g in the surface sediment, and fish concn of 1.41, 4.1, and 12.3 ug/g at the three trophic levels. Gull eggs reached 131 ug/g. In 1985, volatilization of PCB (648 kg) exceeded the sum of all deposition and absorption processes; the lake was losing 185 kg/yr PCB to the atmosphere. The rate of decontamination was about 8.4%/yr. PCBs cycle appreciably between atmosphere and water by wet and dry deposition and volatilization, and between water and sediment by deposition, resuspension, and diffusion. TERRESTRIAL FATE: PCBs are mixtures of different congeners of chlorinated biphenyl and the relative importance of the environmental fate mechanism generally depends on the degree of chlorination(1). In general, the persistence of PCBs increases with an increase in the degree of chlorination. Mono-, di- and trichlorinated biphenyls (Aroclors 1221 and 1232) biodegrade relatively rapidly, tetrachlorinated biphenyls (Aroclors 1016, 1242, and 1248) biodegrade slowly, and higher chlorinated biphenyls (Aroclors 1254 and 1260) are resistant to biodegradation. The position of chlorination in the isomeric classes also determines the extent of biodegradation. Although biodegradation of higher chlorinated congeners may occur very slowly on an environmental basis, no other degradation mechanisms have been shown to be important in soil systems; therefore, biodegradation may be the ultimate degradation process in soil. PCBs have been shown to be strongly adsorbed in soil with adsorption generally increasing with the degree of chlorination(1). Log Koc values for the various congeners range from 4.0 for monochlorobiphenyl to 5.5 for nonachlorobiphenyl(SRC), estimated using a structure fragment constant method(2). However, PCB fluids can penetrate and travel through the cracks and other connected void spaces found in soil formations(3). In the presence of organic material dissolved from soil, the water solubility of PCBs increases which may increase its soil mobility(3). Organic solvents, found at hazardous waste sites, will also increase the solubility and mobility of PCBs(1). Vapor loss of PCBs from soil surfaces appears to be an important mechanism with the rate of volatilization decreasing with increasing chlorination(1). Estimated vapor pressures range from 1.2X10-3 mm Hg for monochlorobiphenyl to 7.6X10-9 mm Hg for nonachlorobiphenyl(2). The low-molecular weight PCBs volatilize more readily than the high-molecular weight species(3). This has lead to an atmospheric enrichment of low-molecular weight isomers in the atmosphere. Likewise, this has lead to the enrichment of high-molecular weight isomers in soil matrices. Vaporization of PCBs from soil decreases as the amount of humic material in the soil increases(3). Humic acid at 500 mg/L in a soil suspension reduced the volatilization of Aroclor 1242 from 3.5% to 2.6%(3). Although the volatilization rate may be low, the total loss by volatilization over time may be significant because of the persistence and stability of PCBs(4). The volatility of PCBs also affects their migration through the soil profile(3). Researchers have carried out simulations that indicate that PCBs can volatilize beneath the soil surface and potentially migrate through several meters of soil cover(3). Volatilization of lower chlorinated and ortho-enriched congeners are greatly enhanced from wet versus dry sand or sediment(5). This was attributed to desorption followed by evaporation-enhanced volatilization(5). AQUATIC FATE: PCBs are mixtures of different congeners of chlorinated biphenyl and the relative importance of the environmental fate mechanism generally depends on the degree of chlorination(1). In general, the persistence of PCBs increases with an increase in the degree of chlorination. Mono-, di- and trichlorinated biphenyls (Aroclors 1221, and 1232) biodegrade relatively rapidly, tetrachlorinated biphenyls (Aroclors 1016, 1242, and 1248) biodegrade slowly, and higher chlorinated biphenyls (Aroclors 1254 and 1260) are resistant to biodegradation. Although biodegradation of higher chlorinated congeners may occur very slowly on an environmental basis, no other degradation mechanisms have been shown to be important in environmental aquatic systems; therefore, biodegradation may be the ultimate degradation process in natural water. In water, adsorption to sediments and organic matter is a major fate process for PCBs(1,2). Experimental and monitoring data have shown that PCB concns are higher in sediment and suspended matter than in the associated water column. The lower chlorinated PCBs will sorb less strongly than the higher chlorinated PCBs. The PCB composition in the water will be enriched by lower chlorinated PCBs because of their greater water solubility while the higher chlorinated PCBs will remain adsorbed to sediment and suspended particles. Volatilization from water surfaces is expected to be an important fate process based upon PCBs estimated Henry's Law constant values ranging from 7.36X10-4 for monochlorobiphenyl to 1.8X10-8 atm-cu m/mole for octachlorobiphenyl(3). Estimated volatilization half-lives for a model river and model lake will range from 2.5 to 70 hrs and 6 to 39 days, respectively. However, volatilization from water surfaces is expected to be attenuated by adsorption to suspended solids and sediment in the water column. This is apparent from the results of two EXAMS model runs, one in which the effect of adsorption was considered, yielding an estimated half-life ranging from 94 days to 2700 yrs in a model pond 2 m deep, and one in which the effect of adsorption was ignored, yielding an estimated half-life ranging from 4 to 13 days(4). Although adsorption can immobilize PCBs for relatively long periods of time in the aquatic environment, re-solution into the water column has been shown to occur on an environmental level suggesting that the substantial quantities of PCBs contained in aquatic sediments can act as an environmental sink for environmental redistribution of PCBs(5,6). The total loss by volatilization over time may be significant because of the persistence and stability of the PCBs. Volatilization of lower chlorinated and ortho-enriched congeners are greatly enhanced from wet versus dry sediment(7). This was attributed to desorption followed by evaporation-enhanced volatilization(7). Aquatic hydrolysis and oxidation are not important processes with respect to the PCBs(2). PCBs have been shown to bioconcentrate significantly in aquatic organisms(8). Researchers studying the bioconcentration of PCBs in fish found that the log BCF ranged from 4.4 for 2-chlorobiphenyl to 6.2 for 2,2',4,4',5,5'-hexachlorobiphenyl(9). As the degree of chlorination increases, biomagnification appears to increase(9). . 477-519 in Contaminated Groundwaters. Adriano DC et al, eds. Northwood, UK: Sci Rev Chpt 16 (1994)]**PEER REVIEWED** ATMOSPHERIC FATE: If released to the atmosphere, PCBs will exist in both the vapor-phase and particulate phase based on estimated vapor pressures ranging from 1.2X10-3 mm Hg for monochlorobiphenyl to 7.6X10-9 mm Hg for nonachlorobiphenyl(1). The vapor pressure of PCBs generally decreases with an increase in the degree of chlorination; therefore, the higher chlorinated PCBs are more likely to be associated with the particulate-adsorption-phase in air than are the lower chlorinated PCBs. This has lead to an atmospheric enrichment of low-molecular weight isomers in the atmosphere(2). Only a small portion of total PCBs are in the vapor phase at any one time in the environment. It has be estimated that the fraction of total PCBs found in the atmosphere consists of only 0.05% of total global PCBs(3). Physical removal of PCBs in the atmosphere is accomplished by wet and dry deposition(4); dry deposition occurs only for PCBs associated in the particulate phase. The PCB concn of rain anywhere in the world may typically range between 1 and 250 ng/l which is an indication of the importance of wet deposition(4). The average rate constant for the vapor-phase reaction of PCBs with photochemically-produced hydroxyl radicals has been estimated to range from 3.5X10-12 to 3.3X10-15 cu cm/molecule-sec at 25 deg C(SRC) using a structure estimation method(5). This corresponds to an atmospheric half-life ranging from 4.6 to 490 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(5). As the degree of chlorination increases, so does the half-life. Although PCBs may be susceptible to photolysis, sufficient experimental data are not available to predict the relative importance of photolysis on an environmental basis(5,6).
Environmental Biodegradation: Measured as a decr in congener concn, clear evidence for anaerobic biodegradation of ambient PCBs was found in untreated Hudson River sediments incubated in the laboratory under a nitrogen atmosphere. Clay encapsulated dredged sediment samples were also taken from the Moreau site. The Moreau sediment contained total PCB concn of 936 + or - 15 mg/kg dry wt, while the river sediment contained 707 + or - 14 mg/kg dry wt. About 53% of the total PCBs (375 mg/kg sediment dry wt), mainly mono to pentachlorobiphenyls, was degraded in the biphenyl amended Hudson River sediments and 30% (281 mg/kg sediment) in biphenyl amended Moreau sediments after 7 mo, with the spectrum of congeners degraded much broader in Hudson River than Moreau sediments. Biphenyl amendment enhanced the disappearance of highly chlorinated congeners. Inoculation with the mixed culture showed positive results in Moreau sediments but not in Hudson River sediments. Regardless of treatments, no biodegradation occurred in a carbon dioxide/hydrogen atmosphere. Moreau sediments incubated in situ (from November to June) showed little change in congener concn in all treatments. The microbial mineralization of three chlorophenols and a PCB mixture was studied using natural bacterial assemblages in laboratory model systems. The systems consisted of water and surface sediment from two lake types: one with a high content of humic substances and the other with a low content. Final PCB concn in the model systems was 38 ug/l. Aerobic mineralization of the (14)C-ring-labelled compounds was determined as production of (14)CO2 in the systems over the course of 60 days. Mineralization of PCBs in the systems was low compared to the aromatics. The breakdown of PCB was 0.047 nM in the humic cultures and 0.052 nM in cultures from the clear water lake. The avg mineralization rates of PCBs over the 60 day test period for the clear-water and humic cultures were 1.1 and 1.2 pM/day. More than 90% of the PCBs adsorbed to the sediment, while less than 1% was found in the water phase. Results of a biodegradation screening procedure utilizing biological oxygen demand dilution water, settled domestic wastewater inoculum, 5-10 ppm test compound and 28 days of incubation of the individual Aroclors were as follows (% biodegraded): Aroclors 1221 and 1232 (100%), Aroclor 1016 (13-48%), Aroclor 1242 (0-66%), Aroclors 1248, 1254, and 1260 (0%)(1). Reviews of available PCB biodegradation data have reported that mono-, di-, and tri-isomers (Aroclors 1221 and 1232) biodegrade relatively rapidly, tetra-isomers (Aroclors 1016 and 1242) biodegrade slowly and higher PCBs (Aroclor 1248, 1254,and 1260) are resistant to biodegradation(2,3). The position of chlorination in the isomeric classes also determines the extent of biodegradation. For example, PCBs containing all of the chlorines on one ring are degraded faster than PCBs containing the chlorines distributed between both rings(4). Furthermore, chlorines in the ortho positions are also more resistant(4). The rate of PCB dechlorination usually occurs in the following order: meta > para > ortho(5). Soil and river sediment microbial degradation studies have determined that monochlorobiphenyls are moderately biodegraded in contrast to ortho-substituted biphenyls, and that reductive dechlorination occurs primarily at the meta and para positions(1). The rate and extent of dechlorination tends to decrease with increase in halogenation(1). In a study of the biodegradation of PCBs in freshwater sediments, researchers discovered that some anaerobic microbial communities performed o,m,p-dechlorinations based on the redox potential of the PCB congener(2). Some anaerobic microbial communities biodegraded o,m-PCBs based on the molecular shape resulting in the enrichment of o-PCBs. This type of selective biodegradation has been observed in other anaerobic studies as well. It appears that the dechlorination of specific PCB congeners may be an alternative source of energy for the anaerobic community(2). Reductive dechlorination of PCBs is a favorable process in anaerobic systems due to the fact that PCBs act as an electron sink, thereby allowing reoxidation of metabolic intermediates(3). Anaerobic microbial communities in sediments have been observed to dechlorinate PCBs at rates of 3 ug Cl/g sediment per week at 12 deg C(3). The rate of PCB dechlorination usually occurs in the following order: meta > para > ortho. Optimum rates of PCB dechlorination usually occur for concns in the range of several hundred to 1,000 ppm (w/w) of sediment(3). Below 50 ppm, dechlorination is often very slow or non-measurable(3). Dechlorination of PCB occurs at temperatures ranging from 12-25 deg C while temperatures above 37 deg C show no dechlorination(3). In general, mono- and dichlorobiphenyls tend to accumulate after the dechlorination of the other higher chlorinated species under anaerobic conditions. To further degrade these compounds, aerobic conditions may need to be present. Biodegrading organisms may not have access to PCBs as they may be dissolved in the organic phase of soils or sediment and could be protected under waxy layers of aged organic matter. Often times, other contaminants such as oil and grease, heavy metals, and solvents are present with PCBs. These contaminants can inhibit the biodegradation of the PCB congeners(3). Low rates of dechlorination in sediments has been associated with large concns of oil and grease. The aerobic biodegradation of mono-, di-, and trichlorobiphenyl PCBs in the presence of biphenyl was studied using psychrotrophic microorganisms found in Arctic regions of Canada(1). After 6 weeks of incubation at 30 deg C in a soil slurry, PCB degradation was extensive. All monochlorobiphenyls as well as 2,4-, 2,5-, 3,4-, and 3,4'-dichlorobiphenyl were completely removed. However, there was little or no degradation of 2,2'- and 3,3-dichlorobiphenyl. Degradation of the trichlorobiphenyls, 2,3,4'- and 2,3',4-trichlorobiphenyl ranged from 40-90%. Other trichlorobiphenyls such as 2,2',5-, 2,3',4-, and 3,4,4'-trichlorobiphenyl showed relatively no biodegradation(1).
Environmental Abiotic Degradation: PHOTOCHEMICAL DEGRADATION MAY BE ONE ROUTE OF THEIR BREAKDOWN IN THE ENVIRONMENT: PHOTOCHEMICAL EXPERIMENTS CONDUCTED UNDER SIMULATED NATURAL CONDITIONS ON ... COMMERICAL PCB PREPARATIONS HAVE INDICATED SEVERAL DEGRADATIVE REACTIONS, SUCH AS DECHLORINATION, POLYMERIZATION & SOLVOLYSIS. The average rate constant for the vapor-phase reaction of PCBs with photochemically-produced hydroxyl radicals has been estimated to range from 3.5X10-12 for monochlorobiphenyl to 3.3X10-15 cu cm/molecule-sec for nonachlorobiphenyl at 25 deg C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life ranging from 4.6 to 490 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). As the degree of chlorination increases, so does the half-life. Abiotic transformation processes such as hydrolysis and oxidation do not significantly degrade PCBs in the aquatic environment(2,3). Although PCBs may be susceptible to photolysis, sufficient experimental data are not available to predict the relative importance of photolysis on an environmental basis(4).
Environmental Bioconcentration: Polychlorinated biphenyls (PCBs) are highly lipophilic and bioconcentrate in tissue from concentrations in water ... Bioconcentration kinetics of a single polychlorinated biphenyl (PCB), Aroclor 1260, from water was studied with an estuarine fish species, Cape stumpnose (Rhabdosarqus holubi). Ten to twelve fish were placed in 50 l aquaria and exposed with PCB concentrations of 10, 1, or 0.5 ug/l. Exposures were for 90 days followed by a depuration period of 90 days. Chromatographs revealed that the Aroclor 1260 was not metabolized by the fish. A rapid initial uptake of PCB by fish was shown, with an almost linear increase in concentration during the first 20 to 30 days of exposure. A plateau or equilibrium level was evident at about 90 days. Bioconcentration factors for an exposure of 1 ug/l were 1100, 5900, and 24,000 for 20, 30, and 90 days exposure, respectively. After 90 days depuration, the depuration rate was 0.014 per day and the half-life was 50 days. The bioaccumulation potential of three toxic coplanar polychlorinated biphenyl (PCB) isomers was investigated using green-lipped mussels (Perna viridis L) as a bioindicator, by transplanting 500 individuals from a relatively uncontaminated area to the heavily polluted Hang Hau, Junk Bay, Hong Kong. The compounds were 3,3',4,4'-tetrachlorobiphenyl, 3,3',4,4',5,-pentachlorobiphenyl, and 3,3',4,4',5,5'-hexachlorobiphenyl. Samples were collected at 0, 1, 2, 4, 6, 8, 10, 12, 14, 16, and 17 days. At 17 days, remaining mussels were back-transplanted to the original cleaner waters and further sampled during the depuration period at 0, 3, 6, 14, and 32 days. Highest levels of each PCB isomer was found on days 0 or 3 of the back-transplantation period. Maximum wet weight value for total PCBs was 630 ng/g. Maximum lipid weight value for total PCBs was 45,000 ng/g. Control mussels from the clean water contained 200 to 230 ng/g total PCBs; from the polluted water, 28,000 to 35,000 ng/g total PCBs. PCB levels at the end of the 32-day depuration period were higher than pre-exposure levels. Available experimental data (by PCB congener) has reported the following average log bioconcentration factors for aquatic organisms: mono- (3.26), di- (3.61), tri- (3.56), tetra- (3.95), penta- (4.14), and hexachlorobiphenyl (5.27)(1). A review of available laboratory experimental data (by specific Aroclor) has reported the following log bioconcentration factors for aquatic organisms: Aroclor 1016 (4.53-4.63), Aroclor 1254 (4.43-5.02), Aroclor 1260 (5.28)(1). Researchers studying the bioconcentration of PCBs in fish found that the log BCF ranged from 4.4 for 2-chlorobiphenyl to 6.2 for 2,2',4,4',5,5'-hexachlorobiphenyl(1). As the degree of chlorination increased, biomagnification appeared to increases(1). However, the more highly chlorinated PCB isomers do not accumulate in plants to the same degree as the lower chlorinated isomers(1). In one BCF study, striped bass were exposed to varying concns of PCBs in different forms(2). The study included striped bass being exposed to water contaminated with 0.1 and 1.0 ng/ml of PCBs, being fed a diet contaminated with PCBs at 4.0 and 40 ng/g, and both PCB contaminated water and feed(2). During a 40 day exposure period, PCB concns in striped bass reached their highest values after 20 days at which time PCB exposure was ended and the fish placed in PCB-free water and fed uncontaminated food. Striped bass fed 4.0 and 40 ng/g contaminated food had PCB concns (ng/g wet weight) of 87 and 240, respectively, after 20 days. Striped bass exposed to water contaminated with 0.1 and 1.0 ng/ml PCB had concns (ng/g wet weight) of 140 and 410, respectively, after 20 days. Striped bass fed 4.0 ng/g contaminated food and exposed to 0.1 ng/ml PCB contaminated water had a PCB concn (ng/g wet weight) of 160 after 20 days. Striped bass fed 40 ng/g contaminated food and exposed to 1.0 ng/l PCB contaminated water had a PCB concn (ng/g wet weight) of 570 after 20 days(2). During the depuration of the striped bass in which they were introduced to a PCB free environment, PCB concns in fish tissue decreased. The greatest amount of depuration (70.99%) after 20 days occurred in fish that were fed 40 ng/g contaminated food and exposed to 1.0 ng/ml PCB contaminated water, while the least amount of depuration (31.25%) after 20 days occurred in fish exposed to 1.0 ng/ml PCB contaminated water. The bioconcentration (wet weight basis) in humans has been found to range from 139 to 227(3).
Soil Adsorption/Mobility: MICROBIAL DEGRADATION & VOLATILITY OF POLYCHLORINATED BIPHENYLS (PCBS) WERE DETERMINED. ADSORPTION WAS CORRELATED TO THE TOTAL CHLORINE CONTENT & SURFACE AREA OF EARTH MATERIAL (SOIL, CLAY, SAND). PCBS WERE IMMOBILE WHEN LEACHED WITH WATER OR LANDFILL LEACHATE BUT WERE INTENSELY MOBILE WHEN LEACHED WITH ORGANIC SOLVENTS. HIGHER CHLORINATED ISOMERS ARE LESS MOBILE & MORE PERSISTENT IN THE ENVIRONMENT THAN LOWER CHLORINATED ISOMERS. PCB mobility in aqueous soil-sediment systems has reported experimental Koc values ranging from 510 to 13,300,000 for a variety of Aroclors and PCB congeners; reported Koc values were mostly above 5000(1). Log Koc values for the various congeners range from 4.0 for monochlorobiphenyl to 5.5 for nonachlorobiphenyl(SRC), estimated using a structure fragment constant method(2). Reviews of the PCB mobility literature have found that adsorption of PCBs to soil and sediment generally increases with an increase in the degree of chlorination(3,4). Using soil TLC, column leaching and five different soils, PCBs were found to be generally immobile when leached with water or aqueous landfill leachate, but highly mobile when leached with organic solvents(5). PCB fluids can penetrate and travel through the cracks and other connected void spaces found in soil formations(6). In the presence of organic material dissolved from soil, the water solubility of PCBs increases which may augment its leachability(6). Organic solvents, found at hazardous waste sites, will also increase the solubility and mobility of PCBs(4). Environmental releases of PCBs often accompany releases of carrier materials from utility equipment(6). The PCBs that are present in the mineral oil-PCB mixture become even less water soluble than before. This is due to the PCB partitioning into the mineral oil and the reduced interaction of the PCBs with precipitation or groundwater caused by the hydrophobic nature of the oil matrix(6). The volatility of PCBs also affects their migration through the soil profile(6). Researchers have carried out simulations that indicate that PCBs can volatilize beneath the soil surface and potentially migrate through several meters of soil cover(6).
Volatilization from Water/Soil: WATER: Researchers studied the volatilization half-lives of a number of different Aroclor's in aqueous media; volatilization half-lives ranged from 10-12 days for volatilization from pure water and up to 52 days for volatilization of Aroclor 1260 from river water(1). The Henry's Law Constants for the individual chlorobiphenyl components of Aroclors 1242, 1254, and 1260 were found to vary from 3.3X10-4 to 5X10-5 atm-cu m/mole at 20 deg C with the Henry's constant for each Aroclor mixture approximately 2X10-4 atm-cu m/mole(2). The average Henry's Law Constants of Aroclor 1221, 1242, 1248, 1254, 1260, and 1268 at 25 deg C were found to vary from 2.28X10-4 to 4.4X10-4 atm-cu m/mole; reduction of Henry's Constant by one order of magnitude was predicted to result if the temperature was reduced by 25 deg C(3). Estimated Henry's Law constant values range from 7.36X10-4 for monochlorobiphenyl to 1.8X10-8 atm-cu m/mole for octachlorobiphenyl(4). Estimated volatilization half-lives for a model river and model lake will range from 2.5 to 70 hrs and 6 to 39 days, respectively. However, volatilization from water surfaces is expected to be attenuated by adsorption to suspended solids and sediment in the water column. This is apparent from the results of two EXAMS model runs, one in which the effect of adsorption was considered, yielding an estimated half-life ranging from 94 days to 2700 yrs in a model pond 2 m deep, and one in which the effect of adsorption was ignored, yielding an estimated half-life ranging from 4 to 13 days(5). SOIL: Vapor loss of Aroclor 1254 from clay soil was negligible over a 4 week period, but vapor loss from sand varied from 10-75% over the same period with evaporation of the lower chlorinated congeners occurring at the faster rates(1). Vapor loss of Aroclor 1254 from three different soils was observed to be 40-50% over 2-4 months(2). Hexachloro- and heptachlorobiphenyls volatilized more slowly from sand than pentachlorbiphenyl which volatilized at only half the rate of tetrachlorobiphenyls(2).
Environmental Water Concentrations: A NATIONAL SURVEY CONDUCTED IN USA SHOWED THAT PCB LEVELS IN UNFILTERED WATER SAMPLES DURING 1971-1974 RANGED BETWEEN 0.1 & 3.0 UG/L. An incident was described in which polychlorinated biphenyls (PCB) from an electro-industrial plant waste tip draining into groundwater channels in karst terrain contaminted a potable water source. PCB composition data were obtained using quadropole gas chromatography-mass spectrometry and capillary gas chromatography. The average level of PCB determined in water was 0.3 ug/l and in sediment 55 ug/g. Concn of polychlorinated biphenyls (PCBs) and other contaminants were determined on large vol surface water samples collected throughout Lakes Ontario, Erie, Huron, and Superior in the spring of 1986. PCB mean sample concn were 0.37 (Lake Superior), 0.631 (Lake Huron), 0.688 (Georgian Bay), 1.378 (Lake Erie), and 1.410 ng/l (Lake Ontario). Minor north-south gradients in contaminant concn in Lake Superior appeared largely a function of differences in atmospheric loading. In contrast, large gradients were evident in Lake Erie, a result of numerous tributary point sources, particularly in the western basin. The Niagara River was the most important in determinant of spatial patterns of contaminants in Lake Ontario. In preparation of remedial action plans for the St. Clair, Detroit, and St. Mary's rivers, a planning-level methodology for evaluation of pollutant loadings from urban nonpoint sources was developed and applied in 3 Canadian cities: Sarnia, Sault Ste. Marie, and Windsor. This methodology uses computed annual volumes of runoff and mean constituent concn, estimated from field sampling, to produce estimates of annual pollutant loadings. The mean stormwater concn and point source equivalent concn (ug/l) for polychlorinated biphenyls (PCBs) were 0.179 and 0.179 for Sarnia, 0.0269 and 0 for Sault Ste. Marie, and 0.0888 and 0.641 for Windsor, respectively. DRINKING WATER: A total PCB level of 0.8 ppb was found in the finished water of Waterford Water Co (Hudson River source) in Sept 1977(1). Five finished waters of 113 USA cities had detections of PCBs (concn 0.1-1.4 ppb) during the three phases of the National Organics Monitoring Survey (NOMS)(2). Fort Edward, NY (on a highly polluted section of the Hudson River) public water supply system had the following total PCB levels: Christie Reservoir - not detected; Dority Reservoir - 70 to 130 ng/l; not detected in ground or surface water on near by Burden Lake(3). In raw tap water in the Waterford, NY treatment plant, which also has the Hudson River as its source, mean PCB levels in 1976 were 0.12 ug/l (range: 0.05-0.24)(4). GROUNDWATER: A concn of 0.1 ppb PCB (at the detection limit) was found in a single ground water supply in each of phases II and III of the National Organics Monitoring Survey (NOMS) of the drinking water of 113 USA cities(1). Thirty-two of 163 wells monitored in industrialized areas of NJ were found to contain PCBs with levels ranging from 0.06-1.27 ug/l(2). SURFACE WATER: Mean PCB concns of 0.63-3.3 ng/l were detected in the waters of Western Lake Superior during 1978-1983(1). Mean levels of 25-38 ng/l were detected in waters collected from 11 agricultural watersheds in Ontario during 1975-77(2). Analysis of water from 8 sites in Galveston Bay found an average PCB level of 3.1 ng/l between 1978-79(3). SEAWATER: PCB levels of < 0.1-2.5 ng/l were detected in the open waters of the Mediterranean Sea during 1977-79(1). Seawater collected from 50 stations in the English Channel/North Sea area in 1983 was found to contain PCB levels ranging from < 2.0-39.0 ng/l(2). Seawater from the Antarctic collected between 1980-82 contained PCB levels of 0.035-0.069 ng/l(3). North Pacific seawater was found to contain levels of 0.04-0.59 ng/l(4). RAIN/SNOW: Precipitation samples collected throughout Canada during 1975-76 contained PCB levels from 0-45 ug/l(1). A review of reported monitoring data found the following typical atmospheric precipitation concns (ng/l) of PCBs at various locations: urban (10-250), rural (1-50), Great Lakes (10-150), marine (0.5-10), remote (1-30)(2). Analysis of rainwater from two open-lake locations in Lake Superior in 1983 found PCB levels of 0.6-48.0 ng/l(3). Snow and ice from Antarctica was found to contain levels of 0.16-1.0 ng/l(4). Levels up to 158 ug/l (1975-78) found in Canada, USA and Europe with levels decreasing to 1986 (PCBs)(5). Total PCB concns in the snow cover on the Agassiz Ice Cap, Ellesmere Island, Canada in May for 1986 and 1987 was 972 and 648 pg/l, respectively(6). The decrease in concn is thought to be attributed to the lower chlorinated congeners volatilizing into the atmosphere. Median winter deposition rates for PCBs in the spring of 1986 in Canadian Arctic snow pack was 73 ng/sq m yr and 95 ng/sq m yr in 1987(6). Annual deposition rates for PCBs in precipitation over Lake Superior, Central Ontario, North Saskatchewan, South Alberta and South British Columbia were 1,2-4.9, 1.6, 1.5-1.7, 1.2, and 1.0 ug/sq m yr, respectively(6).
Effluent Concentrations: Analysis of sewage sludge from 23 American cities found PCB levels ranging from 0.15-3.1 ppm(1). The average PCB concn (Aroclor 1242 + 1260) emitted from gas vents at a hazardous waste landfill in NC was found to be 126 ug/cu m(2). PCB concns of 0.01-1.5 ppm were detected in the fly ash from five municipal incinerators operating under different technological and working conditions(3). PCB levels of 0.3-3.0 ug/cu m were detected in the stack effluents from several midwest municipal refuse and sewage incinerators(4). The total PCB concn measured in the flue gas effluent from a municipal refuse incinerator in OH was 0.26 ug/cu m(5).
Sediment/Soil Concentrations: /IN 1972/ ... SURVEY OF AGRICULTURAL SOILS THROUGHOUT USA ... ONLY 0.1% SAMPLES CONTAINED DETECTABLE LEVELS OF PCB'S. IN URBAN AREAS, FREQUENCY & LEVELS ... WERE HIGHER: 12 OF 19 SOIL SAMPLES FROM METROPOLITAN AREAS (63%) SHOWED DETECTABLE LEVELS. Polychlorinated biphenyls (PCBs) were among anthropogenic organic contaminants measured in 33 sediment samples collected in the Trenton Channel of the Detroit River, connecting Lake St. Clair and Lake Erie. Analysis was by electron capture, negative ionization gas chromatographic mass spectrometry. Total PCB (sum of Cl3 to Cl10 homologs) concentrations ranged from none detected to 13,000 ng/g dry weight of sediment at Station 77 (near Monguagon Creek and the Federal Marine Terminal) and 14,000 ng/g near Elizabeth Park. The PCBs were skewed toward the higher chlorine homologs (Cl8 to Cl10). Sediment samples collected at the shore of Fighting Island and on the southern shore of Gross Ile showed <100 ng/g of PCBs. The concentrations of polychlorinated biphenyl congeners were determined in Lake Ontario sediments. Surficial sediments had a reasonably uniform contaminant distribution throughout the sedimentation basins, with no strong plumes to sources. Mean concentrations of polychlorinated biphenyls (ng/g) in the basins of Lake Ontario were 510 + or - 160 in Niagara, 690 + or - 220 in Mississauga, 630 + or - 340 in Rochester, and 200 + or - 150 in Kingston. Sediment samples outside the sedimentation basins displayed very low contaminant concentrations, averaging of 4 ppb. Sediment trap studies showed that a considerable amount of sediment resuspension occurs in the lake, especially when it is unstratified during the winter. Sediment core studies showed peak discharges of the contaminants occurred in the late 1960s, in good agreement with production and usage history. Using gas chromatography with a (63)Ni electron capture detector on a capillary column, polychlorinated biphenyls were analyzed in surface soil samples (0.5 cm) collected from 49 different locations (remote, rural and urban) in Wales in order to define the background levels of contamination. The polychlorinated biphenyl concentrations ranged from < 0.2 to 12.2 ug/kg of soil, with mean and median of 3.1 and 2.5 ug/kg, respectively. The higher levels were found in soil samples collected from the industrial south east of Wales. Soil properties, such as organic matter or clay content, were not found to correlate with the polychlorinated biphenyl content of the soils. Two sediment cores were taken from the Rochester Basin of eastern Lake Ontario and analyzed for several high molecular wt chlorinated hydrocarbons (including PCB's). The 2 sites are geographically proximate but differ in sedimentation rate, permitting sedimentation dependent processes to be factored out. Vertically integrated numbers of deposit feeding oligochaete worms and burrowing organisms are insufficient to homogenize the sediment on the time scale of PCB inputs, which are non steady state. Accumulation and diagenesis of PCBs was examined in the 2 cores, where bioturbation is inferred from radionuclide profiles and organism density. The apparent molecular diffusion coefficient modeled for PCB was about (1 to 3)X10-9 sq cm/sec. The PCB profiles are characterized by a subsurface peak, decr concn to the surface, and an exponential decr in concn below. The concn peaks occur at 3 to 6 cm in the 2 cores. PCB accumulation rates in these cores incr dramatically in the early 1950s, peak in 1966 to 1969 at approx 40 ng/sq cm-yr, and decr to recent rates of 10 to 20 ng/sq cm-yr, perhaps 50% of which is due to upward mixing by oligochaetes. The PCB accumulation rates for 1980 + or - 1 yr are 12.9 and 17.5 ng/sq cm-yr. Mean PCB concns of about 5-60 ug/kg were detected in the soil in the vicinity of a waste treatment and incineration facility in the United Kingdom during 1984-86 monitoring(1). Analysis of soils from 37 states in 1972 found PCBs in only 2 of 1483 samples, however, the detection limits were only 0.05-0.1 ppm(2). Sediment cores from Milwaukee Harbor (0-80 cm depth) contained PCB levels of 1.03-13.4 mg/kg(3). Analysis of 99 soil samples from urban and rural sites in Great Britain to determine background levels found PCB levels of 2.3-444 ppb with mean and median values of 22.8 and 7.2 ppb, respectively(4). PCB levels of 0-1200 ug/kg were detected in the bottom material of 19 selected streams in the Potomac River Basin(5). Levels of 98-540 ng/g detected in surface sediments of four remote high altitude lakes in the Rocky Mt National Park(6). PCB concns ranging from <1-33 ppb were detected in the soils of the Everglades National Forest in FL(7). A large spill consisting of a mixture of 30% Aroclor 1254 and 70% trichloro/tetrachlorobenzene occurred some time before the summer of 1976 in Saskatchewan, Canada(1). It was estimated that the size of the spill was somewhere between 6,800 and 21,000 liters. Soil samples from the area contained PCBs ranging from 400 mg/kg to 3,000 mg/kg(1). The use of Aroclor 1268 at a former chlor-alkali plant in coastal Georgia (United States) has resulted in extensive contamination of soils on-site and also of sediments in the adjacent brackish marsh(2). This particular brand of Aroclor 1268 consisted mainly of octa- (45%), nona- (35%), hepta- (10.1%), and decachlorobiphenyl (4.8%). Concns of total PCBs in excavation soil, marsh left- and right-transect sediments, and tidal creek sediments were 567, 481, 276 and 9.6 ug/g dry wt, respectively(2). Researchers observed that the levels of PCB concns decreased rapidly relative to the distance from the initial spill. Concns decreased 50 fold over the course of 500 meters suggesting that the marsh environment attenuated the movement of the PCB contamination. At an NPL (National Priorities List) site in Palmer Massachusetts where a waste oil refinery and solvent recovery plant had once existed, millions of gallons of hazardous waste were left behind in tanks and lagoons(3). Soil samples from the site contained both Aroclor-1248 and -1260 at concns up to 30 ppm and up to 80 ppm in oil samples taken from a dike. Soils from the wetland bordering the site contained up to 5 ppm of PCBs(3).
Atmospheric Concentrations: Fourteen chromatographically well-separated PCB congeners were analyzed in filtered air, in particulates, and in rain collected simultaneously in the city of Kiel, FRG. Data are presented on 4 sets of PCBs. The PCB mixture was dominated by congeners with a low degree of chlorination in filtered air and by congeners with a high degree of chlorination (n Cl = 4 to 6) in aerosols and in rain. The summation of PCB concn were in the range 477 to 4947 pg/cu dm. The composition of PCB mixtures in rain samples was remarkably constant, similar to findings for the vapor phase and aerosols. The vapor phase represented up to 99% of total atmospheric concn for the most volatile congeners. Particle scavenging was the dominant source of PCBs in rain, despite the small contribution (only 1 or 2%) of particulate PCBs to the total atmospheric concn. PCB levels of 4.4 and 7.1 ng/cu m were found in the ambient air of Columbia, SC and Boston, MA, respectively, in 1978(1). A review of reported monitoring data found the following typical atmospheric concns (ng/cu m) of PCBs at various locations: urban (0.5-30), rural (0.1-2), Great Lakes (0.4-3), marine (0.05-2), remote (0.02-0.5)(2). The total mean Aroclor concn in the indoor air of a number of public buildings (schools, offices) using PCB transformers in Minnesota during 1984 was found to be nearly twice as high as buildings not using PCB transformers (457 vs 229 ng/cu m) with all indoor air levels significantly higher than typical ambient outdoor air levels(3). Analysis of ambient air at Syowa Station, Antarctica between 1981-82 found PCB levels of 0.02-0.18 ng/cu m(4). PCB levels in indoor air may be high relative to outside air, especially where pre-1972 fluorescent lighting and video display terminals are being utilized; also in buildings equipped with transformers containing PCBs(5).
Food Survey Values: ... FISH, CHEESE & BY-PRODUCTS USED IN ANIMAL FEED WERE THE MAIN COMMODITIES IN USA THAT WERE CONTAMINATED WITH PCB'S. THE PCB CONTENT OF ALL FOOD ITEMS EXCEPT FISH DECR BETWEEN 1971-1975: IT WAS ESTIMATED THAT THE PCB CONTENT OF A TEENAGE BOY'S DIET WAS 15 UG/DAY IN 1971 & 8.1 UG/DAY IN 1975. A compilation of PCB amounts in raw agricultural commodities for fiscal year 1970-76, as analyzed by the US FDA and Dept of Agriculture, has been reported as follows (commodity-number samples analyzed, percent positive detections, ave concn positives): (fish-2901, 46.0%, 0.892 ppm), (shellfish-291, 18.2%, 0.056 ppm), (eggs-2303, 9.6%, 0.072 ppm), (red meat-15200, 0.4%, 0.008 ppm), (poultry-11340, 0.6%, 0.006 ppm), (fluid milk 4638, 4.1%, 0.067 ppm), (cheese-784, 0.9%, 0.011 ppm)(1). The results of PCB analysis of ready-to-eat foods collected in markets of a number of USA cities conducted by the US FDA as part of the Total Diet Studies for adults have been reported as follows for recent fiscal years (number of food composites, number with positive detections, ave of concn of positives in ppm): 1981/1982: (324, 2, 0.001), 1980: (360, 2, 0.002), 1979: (360, 4, <0.001-0.002), 1978: (360, 9, trace-0.05)(2-5). In the 1970s, high concns began to appear in dairy products and packaged foods due to a compound called Cumar(1). Cumar contained approximately 18% Aroclor 1254 and was the major source of PCB dairy product contamination as a result of its use to treat silos. Packaged foods were contaminated as a result of PCBs leaching or migrating from the paperboard boxes and liners manufactured from recycled paper, such as self-duplicating copy paper, containing PCBs(1).
Plant Concentrations: Mean PCB concns of about 7-60 ug/kg (dry wt) were detected in foliage in the vicinity of a waste treatment and incineration facility in the United Kingdom during 1984-6 monitoring(1). Concns ranging from < 10 to 812 ng/g (mean about 20-30 ng/g) were detected in plant leaves collected from 15 nations (including USA) during 1984-5(2). Purple loosetrife, from the Hudson River basin in 1986, absorbed PCBs from contaminated soil and emitted the lowest chlorinated PCBs (most volatile) during transportation(3). Purple loosetrife in Hudson River basin absorbed PCBs from contaminated soil in 1986 and emitted the lowest chlorinated PCBs (most volatile) during transpiration(1).
Fish/Seafood Concentrations: Fish in the Hudson River have shown steadily declining PCB values. Large mouth bass (M. salmoides contained up to 145 ug/g fillet in 1977 and 10.2 ug/g fillet in 1981. ... PCBs in 10 mussels (Mytilus edulis), each from 10 sites in Long Island Sound, CO, have also been reported. The mean maxium PCB levels ranged from 0.049-0.115 ppm as wet weight. These are below the 5 ppm limit set by FDA for PCBs in fish and shellfish. the maximum PCB residues in 547 finfish from the Chesapeake Bay and its tributaries during 1976-1980 have also been reported. The concentrations in flesh were as follows (in ppm): in 1976, not detected to 0.98; in 1977, 0.030-0.51; in 1978, 0.06- 4.64; in 1979, 0.01-1.60; and in 1980, 0.003-1.45. ... Fish from USA rivers generally contained <2 ug/g (1980-81): fish containing >2 ug/g wet weight were from the following rivers: the Hudson, Merrimack, Connecticut, Delaware, Mississippi in Minnesota, Ohio and Cape Fear (NC); Lakes containing fish with values above this level were Lakes Michigan, Huron, Erie and Ontario. /Polychlorinated Biphenyls/ Different fish species from 3 inland waters in Alexandria, Egypt, were assayed for residues of organochlorine insecticides and polychlorinated biphenyls (PCBs). The fish obtained from commercial fishermen in 1985 included: Pagellus erythrinus, Sargus vulgarius, Siganus rivulatus, Sphyraena sphyraena, and Trigla herundo from Abu Qir Bay; and Tilapia fish from Idku and Maryut Lakes. Twenty grams of dorsal fish muscle were extracted and the residues analyzed by GLC; reagent blanks and spike samples were included with each sample. The waters from which the fish were obtained receive drainage from industrial, agricultural and urban activities. Water samples were not assayed for specific components. Total PCB residues were the second most predominant contaminant found in all samples and the highest total PCB concentration occurred in Sargus vulgarius from Abu Qir Bay (89.5 ug/kg). All PCBs were found in Tilapia fish from Idku and Maryut lakes. Total PCB concentration in species followed order: Sargus> Sphyraema> Siganus> Pagellus> Trigla. From a health standpoint, all samples were well below permissible levels for PCBs. The bioaccumulation potential of three toxic coplanar polychlorinated biphenyl (PCB) isomers was investigated using green-lipped mussels (Perna viridis L) as a bioindicator, by transplanting 500 individuals from a relatively uncontaminated area to the heavily polluted Hang Hau, Junk Bay, Hong Kong. The compounds were 3,3',4,4'-tetrachlorobiphenyl, 3,3',4,4',5,-pentachlorobiphenyl, and 3,3',4,4',5,5'-hexachlorobiphenyl. Samples were collected at 0, 1, 2, 4, 6, 8, 10, 12, 14, 16, and 17 days. At 17 days, remaining mussels were back-transplanted to the original cleaner waters and further sampled during the depuration period at 0, 3, 6, 14, and 32 days. Highest levels of each PCB isomer was found on days 0 or 3 of the back-transplantation period. Maximum wet weight value for total PCBs was 630 ng/g. Maximum lipid weight value for total PCBs was 45,000 ng/g. Control mussels from the clean water contained 200 to 230 ng/g total PCBs; from the polluted water, 28,000 to 35,000 ng/g total PCBs. PCB levels at the end of the 32-day depuration period were higher than pre-exposure levels. A total of 92 polychlorinated biphenyl congeners (1 to 10 chlorine substitution) were monitored in brown and lake trout, small and large rainbow trout, and small and large coho salmon from Lake Ontario. An average of 54 to 68 congeners were present in whole fish and 33 to 62 in muscle, including the nonochloro substituted compounds which were analyzed as a composite sample. About 15 congeners were not detected in any species; 25 were present at mean levels below 10 ug/kg in most species except in lake trout, which were slightly higher. Highest concentrations were among the pentachlorobiphenyl and hexachlorobiphenyl compounds, with 2,2',4,4',5,5'-hexachlorobiphenyl the most common. Total congener concentrations ranged from 1 to 10 mg/kg in whole fish and from 0.3 to 4 mg/kg in muscle. Consistent values of congener composition were shown when individual congener levels were expressed as percent of total composition. The ten most common congeners represented about 52% of the total content. This value does not appear to be influenced by species or by total concentration. The homologues observed averaged about 56% chlorine by weight in fish and muscle. Similar levels of polychlorinated biphenyls (PCBs) were found in 20 correlated uncooked and cooked (baked) bluefish fillets. Fillets averaged 2.5 ppm PCBs (range, 1.0 to 7.2 ppm) as Aroclor 1254 (whole basis) before cooking; after cooking, with the oil drippings and skin discarded, 2.7 ppm PCBs (range, 0.7 to 4.9 ppm) or 8% greater than the uncooked fish. This higher concentration was a result of weight loss during cooking from oil drippings (5.5%), evaporated moisture (20.2%)< and discarded skin (5.2%). The net reduction in PCB content of fish after cooking and discarding the skin was 27%. Six of the oil drippings had quantifiable PCB levels (mean 8.1 ppm, range 1.5 to 30 ppm). Fillets from 25 white suckers, Catostomus commersoni (4 immatures, 9 females and 12 males), were obtained from a Saginaw Bay, Lake Huron commercial fishery, and were analyzed for polychlorinated biphenyls. Polychlorinated biphenyl levels ranged from 0.01 to 0.18 ppm, with a mean of 0.05 and standard deviation of 0.04. There was no statistically significant correlation between wt of fish and levels of polychlorinated biphenyls. Strontium-90 was measured in the vertebrae of channel catfish (Ictalurus punctatus), collected from an embayment in White Oak Creek, TN and the adjoining Clinch River/Watts Bar Reservoir, in order to determine their exposure to the polychlorinated biphenyl (PCB) and (90)Sr-contaminated effluent entering the embayment from a point source discharge (Oak Ridge National Laboratory). Catfish were collected in July and Aug 1986 from 9 different sampling sites. PCBs were detected in all catfish collected, and the mixtures recovered contained predominantly highly chlorinated congeners characteristic of Arochlor 1254 and 1260. Little of the PCB burden of the fish in the river could be traced to continuing PCB discharges to the embayment. There were no significant differences in mean PCB levels among sampling sites. The highest mean concn of PCBs was 1.4 ug/g, in fish sampled from the Oak Creek embayment. Blubber samples of dolphins collected in the south-east Indian Ocean all show traces of the persistent organochlorine compounds including polychlorinated biphenyls. A total of 133 common dolphin (Delphinus delphis) blubber and 100 bottlenosed dolphin (Tursiops truncatus) blubber samples were analyzed. A difference in the accumulation pattern of polychlorinated biphenyls between males and females was evident. Female cetaceans transfer the major portion of their polychlorinated biphenyl residue load to their offspring through lactation. In males, residue concn in the blubber incr with age, whereas in female cetaceans, the residue concn showed a sharp decline at approx the age of sexual maturity. Residues of polychlorinated biphenyls declined from 1980 to 1985 in the common dolphin. There was a significant difference between polychlorinated concn in the blubber of males of the common dolphin and the bottlenosed dolphin and the juveniles of the two species (P < 0.05). Since the bottlenosed dolphin feeds close to shore and the common dolphin feeds further offshore, this trend seems to indicate a higher contaminant load in the coastal waters than in the open ocean. Toxic non-, mono- and di-ortho coplanar PCB congeners were determined in terrestrial mammals (human, cat and dog), a coastal marine mammal (finless porpoise), and marine mammals (Dall's porpoise, Baird's beaked whale, and the killer whale). Total PCBs were 1.0 ug/g (human), 2.0 (cat), 0.10 (dog), 320 (finless porpoise), 8.6 (Dall's porpoise), 2.3 (Baird's beaked whale), and 370 ug/g wet wt (killer whale). The concn of coplanar PCBs were found to be higher in the order of di-ortho > mono-ortho > non-ortho congeners and were significantly higher than the levels of toxic dioxins and furans. The geographical distribution of these chemicals based on the relative abundance of coplanar PCB congeners with reference to total PCBs did not vary in terrestrial, coastal and open ocean mammals, whereas that of polychlorinated dibenzofurans and polychlorinated dibenzodioxins apparently decr from land to ocean. 2,3,7,8-Tetrachlorodibenzo-p-dioxin toxic equivalent analysis revealed that higher aquatic predators such as cetaceans receive a greater toxic threat from 3,3',4,4',5- and 2,3,3',4,4'-pentachlorobiphenyls than polychlorinated dibenzofurans and polychlorinated dibenzodioxins. Average PCB levels of 0.07-14.5 mg/kg were found in 750 fish samples collected from 11 major lakes and rivers in Alberta, Canada(1). Mean PCB levels of 1.71 mg/kg (wet wt) were found in 100 cod livers taken from Halifax cod in 1980(2). Mean levels of 0.049-0.115 ppm (wet wt) were detected in mussels collected from 10 locations along the CT shoreline in 1983(3). Composite fish samples taken from major tributaries and embayments of Lakes Superior and Huron in 1983 contained levels of 600-72000 ng/g of fish fat(4). PCB levels ranging from 9-419 ug/kg were detected in lobsters from the NY Bight harvest areas(5). Analysis of 62 samples of commercial fish (primarily from Lake Ontario) collected in 1980 found levels of 0.11-4.90 ppm(6). As part of the National Pesticide Monitoring Program, 315 fish were collected from 107 stations nationwide between 1980-81 and found to contain a geometric mean concn of 0.53 ug/g; this concn was lower than previous monitoring in 1976-77 and 1978-79 which found levels of 0.88 and 0.85 ug/g, respectively(7). Fish in the Hudson River have shown steadily declining PCB values. Largemouth bass (M. salmoides) contained up to 145 ug/g fillet in 1977 and 10.2 ug/g fillet in 1981; fish in the Chesapeake Bay contained 980 ppb in 1976 and 3 to 1450 ppb in 1980; overall, fish from USA rivers generally contained <2 ug/g PCBs; rivers in 1980/81 containing fish with PCB conc >2 ug/g wet weight were the Hudson, Merrimack, Connecticut, Delaware, Mississippi in Minnesota, Ohio and Cape Fear, NC; lakes containing fish concn above this level were Michigan, Huron, Erie, and Ontario(8). PCB concn in fish livers taken near the Santa Monica Bay municipal outfall ranged from 1.2 mg/kg in yellowchin sculpin to 2-3 to 16 mg/kg in Pacific Sanddab taken near Malibu Beach(1). Body burdens in lake trout (Salvenlinus namaycush) from the upper Great Lakes have declined from a max of 22.91 mg/kg in 1974 to 5.63 mg/kg in 1982(2). PCB levels of 530 ug/kg were noted in herring muscle tissue (Clupea harengus) netted in the southern part of the Baltic Sea(3). Mean concn of Aroclor 1242, 1254 and 1260 were 1.7, 5.4, and 1.1 ug/g, respectively, in chinnok salmon eggs collected from Lake Michigan fish(4). Trout and scuplin accumulated PCBs as a result of eating contaminated Pacific salmon eggs(5). In 1969, PCBs were identified in fish from the Hudson River and the Great Lakes with the most extensive contamination occurring in Lake Michigan(1). Contaminated fish included lake trout and Coho salmon. In the Hudson River, large mouth bass and striped bass were identified with PCB levels as high as 145 ppm(1). Fish in the Hudson River have shown steadily declining PCB values. Large mouth bass (M. salmoides contained up to 145 ug/g fillet in 1977 and 10.2 ug/g fillet in 1981. ... PCBs in 10 mussels (Mytilus edulis), each from 10 sites in Long Island Sound, CO, have also been reported. The mean maxium PCB levels ranged from 0.049-0.115 ppm as wet weight. These are below the 5 ppm limit set by FDA for PCBs in fish and shellfish. the maximum PCB residues in 547 finfish from the Chesapeake Bay and its tributaries during 1976-1980 have also been reported. The concentrations in flesh were as follows (in ppm): in 1976, not detected to 0.98; in 1977, 0.030-0.51; in 1978, 0.06- 4.64; in 1979, 0.01-1.60; and in 1980, 0.003-1.45. ... Fish from USA rivers generally contained <2 ug/g (1980-81): fish containing >2 ug/g wet weight were from the following rivers: the Hudson, Merrimack, Connecticut, Delaware, Mississippi in Minnesota, Ohio and Cape Fear (NC); Lakes containing fish with values above this level were Lakes Michigan, Huron, Erie and Ontario. /Polychlorinated Biphenyls/
Animal Concentrations: DURING MARCH 1964 AND FEBRUARY 1970, 48 OF 169 GOLDEN EAGLES FROM 22 STATES WERE FOUND TO CONTAIN PCBS IN EITHER BRAIN, HEART, KIDNEY, LIVER, MUSCLE OR FAT, IN CONCN RANGING FROM LESS THAN 1 TO 19 UG/G ON A WET BASIS. /POLYCHLORINATED BIPHENYLS/ Game birds in New York state contained up to 15 ug/g in their subcutaneous fat. /Polychlorinated Biphenyls/ USEPA; Drinking Water Quality Criteria Document: Polychlorinated Biphenyls (PCBs) ECAO-CIN-414 p.IV-27-8 (1987)] Game animals in Spain in 1982-1983, in West Germany, and in Sweden have been shown to contain high polychlorinated biphenyl (PCB) levels. Birds and animals eating earthworms contaminated with PCBs will accumulate PCBs. Three species of duck, red-crested pochard (Netta rufina), common teal (Anas crecca), and spoon duck (Anas clypeata), from the Ebro Delta (Spain) were captured during the hunting seasons 1977 to 1981. The three species differ in behavior and habits. The common teal is the smallest and has the highest metabolic rate. Only Netta rufina is a permanent resident of the delta. Anas clypeata is more carnivorous than Anas crecca or Netta rufina. Five tissues (breast muscle, liver, kidney, adipose tissue, and medulla) were analyzed for PCBs by GC-ECD. PCBs were not detected in the medulla. In Netta rufina, the concentration of PCBs (fat basis) for the seasons 1977-78 (n= 10), 1978-79 (n= 9), 1979-80 (n= 2), 1980-81 (n= 6), and 1981-1982 (n= 4) were as follows: in breast muscle, range 0.00 to 0.44 ug/g; in liver, range 0.00 to 0.21 ug/g; in kidney, range 0.00 to 0.51 ug/g; and in adipose tissue, range 0.00 to 1.92 ug/g. In Anas crecca, the concentration of PCB for the seasons 1977-8 (n= 10), 1978-9 (n= 10), 1979-1980 (N= 5), 1980-81 (n= 17), and 1981-82 (n= 5) were as follows: in breast muscle, 0.31, 7.68, 2.82, 12.29, and 0.29 ug/g, respectively; in liver, 0.64, 4.72, 1.65, 8.04, and 0.53 ug/g, respectively; in kidney, 0.0, 3.60, 0.79, 4.21, and 0.22 ug/g, respectively; and in adipose tissue, 2.97, 15.33, 8.94, 10.36, and 0.86 ug/g, respectively. In Anas clypeata, the concentration of PCB for the seasons 1977-78 (n= 10), 1978-79 (n= 4), 1979-80 (n= 5), 1980-81 (n= 19), and 1981-82 (n= 5) were as follows: in breast muscle, 7.85, 0.45, 0.28, 2.05, and 7.53 ug/g, respectively; in liver, 1.38, 5.59, 3.01, 2.03, and 6.42 ug/g, respectively; in kidney, 0.25, 2.00, 0.51, 13.39, and 8.86 ug/g, respectively; and in adipose tissue, 11.70, 10.44, 1.67, 2.81, and 24.01 ug/g, respectively. Samples of Herring Gull (Larus argentatus) eggs and 5-day-old and 15-day-old chicks were frozen and analyzed for polychlorinated biphenyl (PCB) content. The PCB content of livers of 15-day-old chicks was also determined. PCB content of eggs was 47.5 mg/kg of fat, and of 5-day-old chicks was 26.8 mg/kg of fat. Estimated total body contents of PCBs in egg was 443.7 ug and in 5-day-old chicks 85.3 ug. The body burdens of polychlorinated biphenyls (PCBs) on the basis of n-hexane extractable lipids were determined in North Sea plankton during the declining spring bloom. Total PCB level were 0.22 to 8.3 ug/g n-hexane extractable lipids in zooplankton and 11.8 to 28 ug/g in zooplankton. The PCB patterns of the copepods Calanus finmarchicus and Temora longicornis were dominated by low chlorinated congeners; the distribution in Temora tended toward more highly chlorinated PCBs than in Calanus. Concentrations of PCBs were higher in the British and continental coasts, the Doggerbank, and the region near Bergen. To determine if contaminant levels in Common Terns had changed over the last decade, eggs from 4 nesting colonies on the 3 lower Great Lakes were collected and analyzed during a collaborative study in 1981. Polychlorinated biphenyls were detected in all the eggs from the 4 colonies, with residue values ranging from 1.77 to 17.36 ppm wet wt; eggs from the Lake Ontario colony were the most heavily contaminated while those from the Lake Huron were the least contaminated. Comparisons with data from earlier studies on Common Tern indicated that polychlorinated biphenyl levels in eggs from the 4 sampled colonies had decreased by up to 80-90% from 1969-73 to 1981. Toxic non-, mono- and di-ortho coplanar PCB congeners were determined in terrestrial mammals (human, cat and dog), a coastal marine mammal (finless porpoise), and marine mammals (Dall's porpoise, Baird's beaked whale, and the killer whale). Total PCBs were 1.0 ug/g (human), 2.0 (cat), 0.10 (dog), 320 (finless porpoise), 8.6 (Dall's porpoise), 2.3 (Baird's beaked whale), and 370 ug/g wet wt (killer whale). The concn of coplanar PCBs were found to be higher in the order of di-ortho > mono-ortho > non-ortho congeners and were significantly higher than the levels of toxic dioxins and furans. The geographical distribution of these chemicals based on the relative abundance of coplanar PCB congeners with reference to total PCBs did not vary in terrestrial, coastal and open ocean mammals, whereas that of polychlorinated dibenzofurans and polychlorinated dibenzodioxins apparently decr from land to ocean. 2,3,7,8-Tetrachlorodibenzo-p-dioxin toxic equivalent analysis revealed that higher aquatic predators such as cetaceans receive a greater toxic threat from 3,3',4,4',5- and 2,3,3',4,4'-pentachlorobiphenyls than polychlorinated dibenzofurans and polychlorinated dibenzodioxins. Game birds in New York State contained up to 15 ug/g PCBs in their subcutaneous fat(1). Mean PCB concns of 0.58-7.4 mg/kg (wet weight) were found in the blubber of various types of seals in the Arctic and Nova Scotia during 1981-82 which were slightly lower than levels found 9-11 years earlier(1,2). Carcasses of bald eagles contained 380 ppm (lipid basis) PCBs while eagle brains contained 3.75 ppm(3). Analysis of 38 species of birds (166 samples) taken from 8 western USA states in 1980 found a geometric mean PCB level of 0.03 ppm(4). Collection of 54 waterfowl in NY State between 1981-82 resulted in the measurement of 0.34-124 and 0.05-6.3 ug/g in subcutaneous fat and breast muscle, respectively(5). PCBs were detected in 100% of black duck wings (mean conc 0.12-0.87 ppm) collected from 17 states during the 1981-82 hunting season; positive detection in mallards varied from 9-90% depending on region of the country(6). Analysis of 293 bald eagle carcasses from 32 states between 1978-81 found median PCB levels of 3.0-5.3 ppm(7). Game birds in New York State contained up to 15 ug/g PCBs in their subcutaneous fat(8). High levels of PCB's were found in osprey, gyr falcon and white-tailed eagle (5 ug PCB/l) collected in Norway during 1965-1983(4). Median concn in eggs of white-tailed eagle and goshawk were 13.9 and 12.3 ug/l respectively(9). Eggs of Norwegian seabirds collected in 1983 contained mean PCB levels of 0.36-7.07 ug/g(1). White pelican and western grebe eggs collected in 1981 in Klamath Basin, CA contained mean levels of 0.32-2.21 ppm PCB(2). A mean concn of 1.0 ppm was detected in 81 heron eggs taken from nesting sites in Wyoming and Colorado in 1979(3).
Milk Concentrations: /IN 1970/ ... THE MEAN PCB LEVEL IN HUMAN MILK IN TWO CALIFORNIA CITIES WAS ABOUT 0.06 UG/ML OF WHOLE MILK. ... ANALYSIS OF LIPID FRACTION OF 80 SAMPLES OF HUMAN MILK FROM VARIOUS AREAS OF THE USA SHOWED THAT ALL EXCEPT 2 HAD CONCN ... FROM 0.4-10.6 UG/G. THE AVERAGE CONCN IN ALL SAMPLES WAS APPROX 1.7 UG/G. Milk samples collected from each of 1184 bulk transporters hauling milk from all regions of Ontario were analyzed for polychlorinated biphenyls (PCB) by electron capture gas chromatography from May 1985 to Aug 1986. The number of samples analyzed for PCB residues from the southern, western, central, eastern, and northern part of the province was 316, 328 153, 331, and 56, respectively. Detection limits were dependent on and varied directly with milk fat content. The mean % milk fat for the milk from the southern, western, central, eastern, and northern parts of the province when sampled for PCB residues was 3.75, 3.77, 3.81, 3.67, and 3.92, respectively. The mean PCB residues in ug/kg for the southern, western, central, eastern, and northern part of the province was 19, 12, 15, 13, and 14, respectively. The highest residues of PCB occurred in the southern region. Changes in PCB residues in milk since 1970 show a half-life disappearance of 5.9 yr. Fifty samples of human milk from Finland were found to contain mean PCB levels of 0.016 and 0.45 mg/kg in whole milk fat, respectively(1). Forty human milk samples collected from upstate NY contained a total PCB concn of 26.5 ng/g(2). Human breast milk samples from 31 Egyptian women collected in May 1987 were analyzed for a number of different chlorinated contaminants(3). Aroclor 1254 and Aroclor 1260 were not detected (detection limit = 0.001 ppm) in any of the samples analyzed during this experiment.
Other Environmental Concentrations: The binding of three labeled polychlorinated biphenyl (PCB) congeners to natural levels of dissolved organic carbon was measured in lakes and streams of southcentral Ontario using Sep-Pak C18 columns. The association coefficients, calculated on the basis of dissolved organic carbon, varied by over an order of magnitude among the different freshwaters. These coefficients (ml/g C) were 205 to 8860 for PCB 52 (2,5,2',5'-tetrachlorobiphenyl) and for PCB 153 (2,4,5,2',4',5'-hexachlorobiphenyl) were 10,300 to 170,000. The concn of PCBs were measured during 1983-1985 in precipitation, soils and plants in Essex County, Ontario, Canada. Three sites in Windsor were used: the West Windsor Sewage treatment Plant, the roof of the Leddy Library at the University of Windsor, and a suburban backyard site in east Windsor. The avg PCB concn in urban precipitation (23 ng/l) was lower than that previously reported for urban areas in the Great Lakes basin. Many precipitation samples had no quantifiable concn or PCBs, but several had very high concn (143 ng/l). Precipitation at the west Windsor site had the highest avg PCB concn (30.6 ng/l), although less than the avg urban value of 50 ng/l. Differences between sites and with varying wind directions were not significant (p = 0.27). Annual PCB deposition was estimated to be 25.5 g/ha in the urban area and 2.6 g/ha in the suburbs. One plant and soil sample was taken from each area of a 2.5 min square grid on a map of Essex County. Concn of PCBs in soils were 2 to 3 orders of magnitude greater than in precipitation. In city soils, Aroclor 1260 concn averaged 19.2 ug/kg dry soil compared with 3.5 ug/kg for soils in the rural areas of Essex County . Concn in city soils and Canada goldenrod (Solidago canadensis) roots were consistently higher than those from suburban and rural sites. In the city, root tissues had PCB concn similar to those in soil: 21.4 and 15.5 ug/kg for Aroclors 1254 and 1260. Ratios of urban to suburban concn in soils and precipitation were approx 5:1. Concn of PCBs in plant leaves were relatively similar in urban and suburban areas (1 ug/kg). Serum PCB levels increase by 0.15 ng/ml and milk levels increase by 0.12 ng/g for every 0.45 kg of PCB-contaminated fish consumed, but the rate of fish consumption by the people involved in the study were not stated (1). A direct correlation of PCB concn in human breast milk and the number of contaminated eggs consumed by lactating women has been documented. The half-life of PCBs in human breast milk is reported to be 5 to 8 months, and concn of PCBs in breast milk was 4 to 10 times that in maternal blood. Concns of PCBs in human adipose tissue and milk fat are reportedly 100 to 200 times higher than in serum (1).
Environmental Standards & Regulations:
FIFRA Requirements: For the purposes of this paragraph, the term "polychlorinated biphenyls (PCB's)" is applicable to mixtures of chlorinated biphenyl cmpd, irrespective of which mixture of PCB's is present as the residue. The temporary tolerances for residues of PCB's are as follows: 1.5 ppm in milk (fat basis); 1.5 ppm in manufactured dairy products (fat basis); 3 ppm in poultry (fat basis); 0.3 ppm in eggs; 0.2 ppm in finished animal feed for food-producing animals (except the following finished animal feeds: feed concentrates, feed supplements, and feed premixes); 2 ppm in animal feed components of animal origin, incl fishmeal and other by-products of marine origin and in finished animal feed concentrates, supplements, and premixes intended for food producing animals; 2 ppm in fish and shellfish (edible portion). The edible portion of fish excludes head, scales, viscera, and inedible bones; 0.2 ppm in infant and junior foods; 10 ppm in paper, food-packaging material intended for or used with human food, finished animal feed and any components intended for animal feeds. The tolerance shall not apply to paper food-packaging material separated from the food therein by a functional barrier which is impermeable to migration of PCBs.
TSCA Requirements: Parts 761.1-193 contain the regulations concerning the manufacturing, processing, distribution in commerce, and use prohibitions of polychlorinated biphenyls.
CERCLA Reportable Quantities: Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 1 lb or 0.454 kg. The toll free number of the NRC is (800) 424-8802; In the Washington D.C. metropolitan area (202) 426-2675. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b). /Aroclors/
Atmospheric Standards: Listed as a hazardous air pollutant (HAP) generally known or suspected to cause serious health problems. The Clean Air Act, as amended in 1990, directs EPA to set standards requiring major sources to sharply reduce routine emissions of toxic pollutants. EPA is required to establish and phase in specific performance based standards for all air emission sources that emit one or more of the listed pollutants. Polychlorinated biphenyls is included on this list.
Clean Water Act Requirements: The levels of polychlorinated biphenyls in ambient water which may result in an incremental cancer risk of 1X10-5, 1X10-6, and 1X10-7 over an individual lifetime are estimated to be 0.79 ng/l, 0.079 ng/l, and 0.0079 ng/l, respectively. On the basis of the consumption of aquatic organisms alone, the corresponding levels in ambient water are estimated to be 0.79 ng/l, 0.079 ng/l, and 0.0079 ng/l, respectively. For polychlorinated biphenyls the criterion to protect freshwater aquatic life as derived ... is 0.014 ng/l as a 24 hr average. The concn of 0.014 ng/l is probably too high because it is based on biocencentration factors measured in laboratory studies, but field studies apparently produce factors at least ten times higher for fishes. The available data indicate that acute toxicity to freshwater aquatic life probably will only occur at concentrations above 2.0 ng/l and that the 24 hr average should provide adequate protection against acute toxicity. For polychlorinated biphenyls the criterion to protect saltwater aquatic life as derived ... is 0.030 ng/l as a 24 hr average. The concn of 0.030 ng/l is probably too high because it is based on biocencentration factors measured in laboratory studies, but field studies apparently produce factors at least ten times higher for fish. The available data indicate that acute toxicity to freshwater aquatic life probably will only occur at concentrations above 10.0 ng/l and that the 24 hr average should provide adequate protection against acute toxicity. Polychlorinated biphenyls are designated as a hazardous substances under section 311(b)(2)(A) of the Federal Water Pollution Control Act and further regulated by the Clean Water Act Amendments of 1977 and 1978. These regulations apply to discharges of these substances. This designation includes any isomers and hydrates, as well as any solutions and mixtures containing this substance. Toxic pollutant designated pursuant to section 307(a)(1) of the Clean Water Act and is subject to effluent limitations. The ambient water criterion for PCBs in navigable waters is 0.001 ug/l.
Federal Drinking Water Standards: EPA 0.5 ug/l
State Drinking Water Standards: (NJ) NEW JERSEY 0.5 ug/l
State Drinking Water Guidelines: (AZ) ARIZONA 0.008 ug/l (CT) CONNECTICUT 0.5 ug/l (MN) MINNESOTA 0.04 ug/l (ME) MAINE 0.5 ug/l (WI) WISCONSIN 0.03 ug/l
Soil Standards: Solid waste containing concn of PCBs equal to or greater than 10 mg/kg (dry weight) is incorporated into the soil when applied to land used for producing animal feed, incl pasture crops for animals raised for milk. Incorporation of the solid waste into the soil is not required if it is assured that the PCB content is less than 0.2 mg/kg (actual wt) in animal feed or less than 1.5 mg/kg (fat basis) in milk.
FDA Requirements: For the purposes of this paragraph, the term "polychlorinated biphenyls (PCB's)" is applicable to mixtures of chlorinated biphenyl cmpd, irrespective of which mixture of PCB's is present as the residue. The temporary tolerances for residues of PCB's are as follows: 1.5 ppm in milk (fat basis); 1.5 ppm in manufactured dairy products (fat basis); 3 ppm in poultry (fat basis); 0.3 ppm in eggs; 0.2 ppm in finished animal feed for food-producing animals (except the following finished animal feeds: feed concentrates, feed supplements, and feed premixes); 2 ppm in animal feed components of animal origin, incl fishmeal and other by-products of marine origin and in finished animal feed concentrates, supplements, and premixes intended for food producing animals; 2 ppm in fish and shellfish (edible portion). The edible portion of fish excludes head, scales, viscera, and inedible bones; 0.2 ppm in infant and junior foods; 10 ppm in paper, food-packaging material intended for or used with human food, finished animal feed and any components intended for animal feeds. The tolerance shall not apply to paper food-packaging material separated from the food therein by a functional barrier which is impermeable to migration of PCBs.
Allowable Tolerances: For the purposes of this paragraph, the term "polychlorinated biphenyls (PCB's)" is applicable to mixtures of chlorinated biphenyl cmpd, irrespective of which mixture of PCB's is present as the residue. The temporary tolerances for residues of PCB's are as follows: 1.5 ppm in milk (fat basis); 1.5 ppm in manufactured dairy products (fat basis); 3 ppm in poultry (fat basis); 0.3 ppm in eggs; 0.2 ppm in finished animal feed for food-producing animals (except the following finished animal feeds: feed concentrates, feed supplements, and feed premixes); 2 ppm in animal feed components of animal origin, incl fishmeal and other by-products of marine origin and in finished animal feed concentrates, supplements, and premixes intended for food producing animals; 2 ppm in fish and shellfish (edible portion). The edible portion of fish excludes head, scales, viscera, and inedible bones; 0.2 ppm in infant and junior foods; 10 ppm in paper, food-packaging material intended for or used with human food, finished animal feed and any components intended for animal feeds. The tolerance shall not apply to paper food-packaging material separated from the food therein by a functional barrier which is impermeable to migration of PCBs.
Chemical/Physical Properties:
Molecular Weight: 291.98-360.86
Color/Form: Lower chlorinated Aroclors (1221, 1232, 1016, 1242, and 1248) are colorless mobile oils. Increasing chlorine content results in mixtures taking on the consistency of viscous liquids (Aroclor 1254) or sticky resins (Aroclors 1260 and 1262). Arclors 1268 and 1270 are white powders. Vary from mobile oily liquids to white crystalline solids and hard noncrystalline resins. The majority of individual PCBs are waxlike or crystalline solids when isolated in the pure state, a few congeners are liquids at room temperature among the mono- and dichlorobiphenyls.
Odor: Practically odorless; mild aromatic odor
Melting Point: 340 to 375 deg C
Density/Specific Gravity: 1.44 at 30 deg C
Spectral Properties: The spectrum for each Aroclor is very complex being a superposition of the spectra for the individual constituents. UV spectral maxima are at 197-222, 214-265, and 267-302 nm, and give strong molecular ions in mass spectra Infrared absorption wavelengths are 1200-300/cm.
Other Chemical/Physical Properties: Solubility in water is extremely low; soluble in oils and organic solvents. With the exception of Aroclors 1221 and 1268, Aroclors do not crystallize upon heating or cooling, but at a specific temperature, defined as a "pour point", change into a resinous state. To facilitate the photolysis of PCBs, researchers studied the degradation rate in the presence of sodium borohydride. Solutions of Aroclors in 90% acetonitrile/water were irradiated under nitrogen at 254 nm. Without the presence of sodium borohydride, 25% of Aroclor 1254 reacted (lost at least one chlorine atom) after approximately 8 hrs while 10% of Aroclor 1260 reacted in about 1 hr and appeared to remain stable. In the presence of sodium borohydride, 100% of Aroclor 1254 reacted in 16 hrs while 73% of Aroclor 1260 reacted within 120 minutes. Since an Aroclor is a variable mixture, literature Kow values will vary. These increase with increasing chlorination. Low Kow= 1 values at 25 deg C: 3.76 (biphenyl), 5.7 (Cl4-PCB's), 6.0 (Cl5-PCB's), 7.0 (Cl6-PCB's), 8.26 (Cl10-PCB's). /Polychlorinated biphenyls/ The most water soluble PCBs (least chlorinated) are enriched in water relative to the original aroclor. /Polychlorinated biphenyls/ Solubility in water varies because Aroclors are variable mixtures. /Polychlorinated biphenyls/ Vapor pressure is variable since Aroclors are variable mixtures; the most highly volatile PCBs (high vapor pressure) will predominate, so that the PCB composition of the vapor will be enriched in the least chlorinated PCB's. /Polychlorinated biphenyls/ PCBs are destroyed at a 2 second residence time at 1200 deg C with 3% excess oxygen and at 105 seconds residence time at 1600 deg C with 2% excess oxygen. ... Parachlorinated-dibenzfurans (PCDFs) and PCB levels declined exponentially >900 deg C at a 2 second residence time. /Polychlorinated biphenyls/
Chemical Safety & Handling:
DOT Emergency Guidelines: Fire or explosion: Some may burn but none ignite readily. Those substance designated with a "P" may polymerize explosively when heated or involved in a fire. Containers may explode when heated. Some may be transported hot. Health: Inhalation of material may be harmful. Contact may cause burns to skin and eyes. Inhalation of asbestos dust may have a damaging effect on the lungs. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control may cause pollution. Public safety: CALL Emergency Response Telephone Number. ... Isolate spill or leak area immediately for at least 10 to 25 meters (30 to 80 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Protective clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection. Evacuation: Fire: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. Fire: Small fires: Dry chemical, CO2, water spray or regular foam. Large fires: Water spray, fog or regular foam. Move containers from fire area if you can do it without risk. Do not scatter spilled material with high pressure water streams. Dike fire-control water for later disposal. Fire involving tanks: Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from engulfed in fire tanks. Spill or leak: Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent dust cloud. Avoid inhalation of asbestos dust. Small dry spills: With clean shovel place material into clean, dry container and cover loosely; move containers from spill area. Small spills: Take up with sand or other noncombustible absorbent material and place into containers for later disposal. Large spills: Dike far ahead of liquid spill for later disposal. Cover powder spill with plastic sheet or tarp to minimize spreading. Prevent entry into waterways, sewers, basements or confined areas. First aid: Move victim to fresh air. Call 911 or emergency medical service. Apply artificial respiration if victim is not breathing. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. Ensure that medical personnel are aware of the material(s) involved, and take precautions to protect themselves.
Skin, Eye and Respiratory Irritations: Irritating to skin and eyes.
Fire Potential: Flame resistant
Fire Fighting Procedures: If material on fire or involved in fire: Extingiush fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Keep run-off water out of sewers and water sources.
Firefighting Hazards: Irritating gases are generated in fires.
Hazardous Reactivities & Incompatibilities: Liquid chlorine reacts exothermically with polychlorinated biphenyl heat transfer liquid.
Prior History of Accidents: The first documentation of human effects as a result of ingestion of PCBs was derived from the Japanese poisoning incident that occurred in 1968. The victims suffered an acute toxicosis from consuming rice oil contaminated with an industrial oil, Kanechlor-400, consisting of a mixture of polychlorinated biphenyls (PCB), polychlorinated dibenzofurans (PCDF), and polychlorinated quinones (PCQ). The average total amount of PCBs consumed was estimated to be approx 2 g, with approx 0.5 g being the least total amount consumed by an affected group of some 325 people at the time. ... The most notable symptoms of Yusho among 189 patients included dark brown pigmentation of nails and skin, follicular accentuation, acneform eruptions, increased eye discharge, increased sweating at the palms and feeling of weakness. ... A mass outbreak of a peculiar skin disease /including pigmentation and acne from eruptions/ was recorded in Taichung and Changwa in Central Taiwan. The cause of the disease was later identified to be the ingestion of rice bran oil contaminated with polychlorinated biphenyls (PCBs), and there were > 1900 victims. Blood PCB levels of 66 affected persons ranged from 11-720 ppb (mean 49 ppb) at approx 9-12 months after consumption of the PCB-contaminated oil.
Immediately Dangerous to Life or Health: NIOSH considers chlorodiphenyl containing 54% chlorine to be a potential occupational carcinogen. /Aroclor 1254/
Protective Equipment & Clothing: ... Workers should be provided with suitable protective clothing: long-sleeved overalls, boots, overshoes and bib-type aprons that cover the boot tops, and gloves. ... Safety glasses with side shields ... for eye protection. Respirators should be used in areas with PCB vapors and during installation and repair of containers and emergency activities. ... PRECAUTIONS FOR "CARCINOGENS": ... dispensers of liq detergent /should be available./ ... Safety pipettes should be used for all pipetting. ... In animal laboratory, personnel should ... wear protective suits (preferably disposable, one-piece & close-fitting at ankles & wrists), gloves, hair covering & overshoes. ... In chemical laboratory, gloves & gowns should always be worn ... however, gloves should not be assumed to provide full protection. Carefully fitted masks or respirators may be necessary when working with particulates or gases, & disposable plastic aprons might provide addnl protection. ... gowns ... /should be/ of distinctive color, this is a reminder that they are not to be worn outside the laboratory. /Chemical Carcinogens/
Preventive Measures: SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place. In a confined space: /The worker/ should wear appropriate protective equipment and be connected by a lifeline harness to an outside worker. Employees should wash their hands before eating, drinking and smoking ... and refrain from such activities in the polluted rooms ... . Nursing /by women exposed to PCB's/ ... should be discouraged because of the high amount of PCB's excreted with milk ... . If material not on fire and not involved in fire: Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Attempt to stop leak if without undue personnel hazard. Personnel protection: Keep upwind. Avoid breathing vapors. ... Do not handle broken packages unless wearing appropriate personal protective equipment. SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning. PRECAUTIONS FOR "CARCINOGENS": Smoking, drinking, eating, storage of food or of food & beverage containers or utensils, & the application of cosmetics should be prohibited in any laboratory. All personnel should remove gloves, if worn, after completion of procedures in which carcinogens have been used. They should ... wash ... hands, preferably using dispensers of liq detergent, & rinse ... thoroughly. Consideration should be given to appropriate methods for cleaning the skin, depending on nature of the contaminant. No standard procedure can be recommended, but the use of organic solvents should be avoided. Safety pipettes should be used for all pipetting. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": In animal laboratory, personnel should remove their outdoor clothes & wear protective suits (preferably disposable, one-piece & close-fitting at ankles & wrists), gloves, hair covering & overshoes. ... clothing should be changed daily but ... discarded immediately if obvious contamination occurs ... /also,/ workers should shower immediately. In chemical laboratory, gloves & gowns should always be worn ... however, gloves should not be assumed to provide full protection. Carefully fitted masks or respirators may be necessary when working with particulates or gases, & disposable plastic aprons might provide addnl protection. If gowns are of distinctive color, this is a reminder that they should not be worn outside of lab. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": ... operations connected with synth & purification ... should be carried out under well-ventilated hood. Analytical procedures ... should be carried out with care & vapors evolved during ... procedures should be removed. ... Expert advice should be obtained before existing fume cupboards are used ... & when new fume cupboards are installed. It is desirable that there be means for decreasing the rate of air extraction, so that carcinogenic powders can be handled without ... powder being blown around the hood. Glove boxes should be kept under negative air pressure. Air changes should be adequate, so that concn of vapors of volatile carcinogens will not occur. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": Vertical laminar-flow biological safety cabinets may be used for containment of in vitro procedures ... provided that the exhaust air flow is sufficient to provide an inward air flow at the face opening of the cabinet, & contaminated air plenums that are under positive pressure are leak-tight. Horizontal laminar-flow hoods or safety cabinets, where filtered air is blown across the working area towards the operator, should never be used ... Each cabinet or fume cupboard to be used ... should be tested before work is begun (eg, with fume bomb) & label fixed to it, giving date of test & avg air-flow measured. This test should be repeated periodically & after any structural changes. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": Principles that apply to chem or biochem lab also apply to microbiological & cell-culture labs ... Special consideration should be given to route of admin. ... Safest method of administering volatile carcinogen is by injection of a soln. Admin by topical application, gavage, or intratracheal instillation should be performed under hood. If chem will be exhaled, animals should be kept under hood during this period. Inhalation exposure requires special equipment. ... unless specifically required, routes of admin other than in the diet should be used. Mixing of carcinogen in diet should be carried out in sealed mixers under fume hood, from which the exhaust is fitted with an efficient particulate filter. Techniques for cleaning mixer & hood should be devised before expt begun. When mixing diets, special protective clothing &, possibly, respirators may be required. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": When ... admin in diet or applied to skin, animals should be kept in cages with solid bottoms & sides & fitted with a filter top. When volatile carcinogens are given, filter tops should not be used. Cages which have been used to house animals that received carcinogens should be decontaminated. Cage-cleaning facilities should be installed in area in which carcinogens are being used, to avoid moving of ... contaminated /cages/. It is difficult to ensure that cages are decontaminated, & monitoring methods are necessary. Situations may exist in which the use of disposable cages should be recommended, depending on type & amt of carcinogen & efficiency with which it can be removed. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": To eliminate risk that ... contamination in lab could build up during conduct of expt, periodic checks should be carried out on lab atmospheres, surfaces, such as walls, floors & benches, & ... interior of fume hoods & airducts. As well as regular monitoring, check must be carried out after cleaning-up of spillage. Sensitive methods are required when testing lab atmospheres. ... Methods ... should ... where possible, be simple & sensitive. ... /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": Rooms in which obvious contamination has occurred, such as spillage, should be decontaminated by lab personnel engaged in expt. Design of expt should ... avoid contamination of permanent equipment. ... Procedures should ensure that maintenance workers are not exposed to carcinogens. ... Particular care should be taken to avoid contamination of drains or ventilation ducts. In cleaning labs, procedures should be used which do not produce aerosols or dispersal of dust, ie, wet mop or vacuum cleaner equipped with high-efficiency particulate filter on exhaust, which are avail commercially, should be used. Sweeping, brushing & use of dry dusters or mops should be prohibited. Grossly contaminated cleaning materials should not be re-used ... If gowns or towels are contaminated, they should not be sent to laundry, but ... decontaminated or burnt, to avoid any hazard to laundry personnel. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": Doors leading into areas where carcinogens are used ... should be marked distinctively with appropriate labels. Access ... limited to persons involved in expt. ... A prominently displayed notice should give the name of the Scientific Investigator or other person who can advise in an emergency & who can inform others (such as firemen) on the handling of carcinogenic substances. /Chemical Carcinogens/
Stability/Shelf Life: ... PCB's are chemically very inert and are stable to conditions of hydrolysis and oxidation in industrial use.
Shipment Methods and Regulations: No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./ The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials. The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article. PRECAUTIONS FOR "CARCINOGENS": Procurement ... of unduly large amt ... should be avoided. To avoid spilling, carcinogens should be transported in securely sealed glass bottles or ampoules, which should themselves be placed inside strong screw-cap or snap-top container that will not open when dropped & will resist attack from the carcinogen. Both bottle & the outside container should be appropriately labelled. ... National post offices, railway companies, road haulage companies & airlines have regulations governing transport of hazardous materials. These authorities should be consulted before ... material is shipped. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": When no regulations exist, the following procedure must be adopted. The carcinogen should be enclosed in a securely sealed, watertight container (primary container), which should be enclosed in a second, unbreakable, leakproof container that will withstand chem attack from the carcinogen (secondary container). The space between primary & secondary container should be filled with absorbent material, which would withstand chem attack from the carcinogen & is sufficient to absorb the entire contents of the primary container in the event of breakage or leakage. Each secondary container should then be enclosed in a strong outer box. The space between the secondary container & the outer box should be filled with an appropriate quantity of shock-absorbent material. Sender should use fastest & most secure form of transport & notify recipient of its departure. If parcel is not received when expected, carrier should be informed so that immediate effort can be made to find it. Traffic schedules should be consulted to avoid ... arrival on weekend or holiday ... /Chemical Carcinogens/
Storage Conditions: PCB material should be stored in closed containers, in ventilated areas ... /SRP: With appropriate air pollution control equipment./ PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practicable to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/
Cleanup Methods: ... Dry sand or earth should be spread on the leak, or spill area. ... Environmental considerations: Land spill: Dig a pit, pond, lagoon, or holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be contained with a flexible impermeable membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash or cement powder. Environmental considerations: Water spill: Use natural deep water pockets, excavated lagoons, or sand bag barriers to trap material at bottom. If dissolved, apply activated carbon at ten times the spilled amount in region of 10 ppm or greater concentration. Remove trapped material with suction hoses. Use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates or greater concentration. Survey reports six case histories employing EPA's hazardous materials spills treatment trailer are reviewed. The trailer's ... treatment system has three mixed-media filters and three activated carbon columns to remove suspended, precipitated, and organic soluble materials. Spills of PCB, pentachlorophenol, kepone, termide (chlordane), heptachlor, aldrin, and dieldrin, toxaphene, and dinitrobutylphenol were treated by the EPA trailer, which was generally successful in mitigating environmental effects by filtering and carbon-adsorption. 90% removal was achieved for 21 of 23 compounds. PRECAUTIONS FOR "CARCINOGENS": A high-efficiency particulate arrestor (HEPA) or charcoal filters can be used to minimize amt of carcinogen in exhausted air ventilated safety cabinets, lab hoods, glove boxes or animal rooms ... Filter housing that is designed so that used filters can be transferred into plastic bag without contaminating maintenance staff is avail commercially. Filters should be placed in plastic bags immediately after removal ... The plastic bag should be sealed immediately ... The sealed bag should be labelled properly ... Waste liquids ... should be placed or collected in proper containers for disposal. The lid should be secured & the bottles properly labelled. Once filled, bottles should be placed in plastic bag, so that outer surface ... is not contaminated ... The plastic bag should also be sealed & labelled. ... Broken glassware ... should be decontaminated by solvent extraction, by chemical destruction, or in specially designed incinerators. /Chemical Carcinogens/
Disposal Methods: SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices. POLYCHLORINATED BIPHENYLS CAN BE DESTROYED BY INCINERATION IF THE TRANSIT TIME IS LONG ENOUGH. DURING INCINERATION HEXACHLOROBENZENE IS FORMED; ITS RATE OF FORMATION INCR AT HIGH TEMP. IN ORDER FOR THE HEXACHLOROBENZENE TO BE DESTROYED, A TEMP OF 950 DEG C IS NEEDED. THIS RESULTS IN THE FORMATION OF A RESIDUE LESS THAN 100 MG OF HEXACHLOROBENZENE/KG. AT 800 DEG C & A TRANSIT TIME OF 2 SEC, A RESIDUE OF ABOUT 1200 MG/KG REMAINS. EXPERIMENTS ON THE COMBUSTION OF POLYCHLORINATED BIPHENYLS (PCB) IN 1 M-LONG TUBE FURNACE INDICATED THAT PCB CONTAINING APPROX 40% CL IS DESTROYED WITHIN 3-4 MIN AT 900-1000 DEG C USING 100% EXCESS AIR. TEMPERATURES GREATER THAN 1000 DEG C ARE REQUIRED TO DESTROY PCB CONTAINING APPROX 60% CL & DISTILLATION RESIDUES ARISING FROM PCB MFR. DOMESTIC WASTE INCINERATORS OPERATING AT 800-900 DEG C ARE UNLIKELY TO PROVE SUITABLE FOR INCINERATING WASTE CONTAINING TRACE AMT OF PCB. PYROLYSIS EXPERIMENTS AT 900 DEG C WITH NOMINAL RESIDENCE TIME OF 3.5 SEC GAVE 40-60% RECOVERY OF CL AS HCL FROM PCB. Polychlorinated biphenyls are waste chemical stream constituents which may be subjected to ultimate disposal by controlled incineration. Incineration /is performed/ at 3000 deg F with scrubbing to remove any chlorine containing products. Investigations were conducted of new and emerging technologies for the disposal of hazardous wastes, ... including molten salt combustion, fluidized bed incineration, high energy electron treatment of trace organic compounds in aqueous solution, the catalyzed wet oxidation of toxic chemicals, dehalogenation of compounds by treatment with ultraviolet (UV) light and hydrogen, UV/chlorinolysis of organics in aqueous solution, the catalytic hydrogenation-dechlorination of polychlorinated biphenyls (PCBs), and ultraviolet-ozone destruction. Theory, specific wastes treated, and economics are discussed. The major technologies investigated in detail were molten salt combustion, fluidized bed incineration, and ultraviolet/ozone destruction. Among wastes treated by emerging technologies are PCBs, various dioxins, pesticides and herbicides, chemical warfare agents, explosives and propellants, nitrobenzene, and hydrazine plus its derivatives. PRECAUTIONS FOR "CARCINOGENS": There is no universal method of disposal that has been proved satisfactory for all carcinogenic compounds & specific methods of chem destruction ... published have not been tested on all kinds of carcinogen-containing waste. ... summary of avail methods & recommendations ... /given/ must be treated as guide only. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": ... Incineration may be only feasible method for disposal of contaminated laboratory waste from biological expt. However, not all incinerators are suitable for this purpose. The most efficient type ... is probably the gas-fired type, in which a first-stage combustion with a less than stoichiometric air:fuel ratio is followed by a second stage with excess air. Some ... are designed to accept ... aqueous & organic-solvent solutions, otherwise it is necessary ... to absorb soln onto suitable combustible material, such as sawdust. Alternatively, chem destruction may be used, esp when small quantities ... are to be destroyed in laboratory. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": HEPA (high-efficiency particulate arrestor) filters ... can be disposed of by incineration. For spent charcoal filters, the adsorbed material can be stripped off at high temp & carcinogenic wastes generated by this treatment conducted to & burned in an incinerator. ... LIQUID WASTE: ... Disposal should be carried out by incineration at temp that ... ensure complete combustion. SOLID WASTE: Carcasses of lab animals, cage litter & misc solid wastes ... should be disposed of by incineration at temp high enough to ensure destruction of chem carcinogens or their metabolites. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": ... small quantities of ... some carcinogens can be destroyed using chem reactions ... but no general rules can be given. ... As a general technique ... treatment with sodium dichromate in strong sulfuric acid can be used. The time necessary for destruction ... is seldom known ... but 1-2 days is generally considered sufficient when freshly prepd reagent is used. ... Carcinogens that are easily oxidizable can be destroyed with milder oxidative agents, such as sat soln of potassium permanganate in acetone, which appears to be a suitable agent for destruction of hydrazines or of compounds containing isolated carbon-carbon double bonds. Concn or 50% aqueous sodium hypochlorite can also be used as an oxidizing agent. /Chemical Carcinogens/ PRECAUTIONS FOR "CARCINOGENS": Carcinogens that are alkylating, arylating or acylating agents per se can be destroyed by reaction with appropriate nucleophiles, such as water, hydroxyl ions, ammonia, thiols & thiosulfate. The reactivity of various alkylating agents varies greatly ... & is also influenced by sol of agent in the reaction medium. To facilitate the complete reaction, it is suggested that the agents be dissolved in ethanol or similar solvents. ... No method should be applied ... until it has been thoroughly tested for its effectiveness & safety on material to be inactivated. For example, in case of destruction of alkylating agents, it is possible to detect residual compounds by reaction with 4(4-nitrobenzyl)-pyridine. /Chemical Carcinogens/ polychlorinated biphenyls and their biodegradation, bioremediation of polychlorinated biphenyls, aerobic degradation of polychlorinated biphenyls and pieper, and anaerobic degradation of polychlorinated biphenyls There is no direct evidence of degradation of PCBs /polychlorinated biphenyls/ in landfill, though slow degradation may well occur. It seems likely, given that the PCBs (which have low water solubility) are deposited in a container from which release will be slow and that free PCBs are adsorbed on sediments, that most landfill sites pose no potential threat to water and that landfill disposal is a satisfactory method. The extra effort to segregate the capacitors is not justified. It is suggested however, that undue concn at any one landfill site should be avoided. As a rough guide: A) If 5 million items are scrapped annually; and B) if they are disposed of with 35 million tons of domestic and industrial waste annually- one may expect one item in every 7 tons, approx equivalent to between 45 and 60 items per 1.000 cu m of landfilled domestic refuse. If the level as revealed by occasional observation were, for example, one item per ton or greater, there might be a case for investigating the cause and, if reasonable practicable, for diverting some of the items elsewhere. Such undue concn could be presumed to be the result of an industrial disposal. Small intermittent quantities which cannot be conveniently handled by incineration may be disposed of by landfill provided similar guidelines on levels and concn as above are observed. Recommendable methods: Incineration & landfill. Not recommendable method: Open burning. Peer review: Incineration must be for more than 2 sec at 1200 deg C or higher for PCB waste. If PCB content of waste is less than 500 ppm any proper waste incinerator can be used as long as temp exceeds 800 deg C for 0.5 sec. Combustion of PCBs can produce dioxins. Incineration at sea is a good method. (Peer-review conclusions of an IRPTC expert consultation (May 1985))
Occupational Exposure Standards:
NIOSH Recommendations: NIOSH considers chlorodiphenyl containing 54% chlorine to be a potential occupational carcinogen. /Aroclor 1254/ NIOSH usually recommends that occupational exposures to carcinogens be limited to the lowest feasible concn. /Aroclor 1254/ Recommended Exposure Limit: 10 Hr Time-Weighted Avg: 0.001 mg/cu m. /Aroclor 1254/
Immediately Dangerous to Life or Health: NIOSH considers chlorodiphenyl containing 54% chlorine to be a potential occupational carcinogen. /Aroclor 1254/
Manufacturing/Use Information:
Major Uses: EPA AUTHORIZED THE USE OF POLYCHLORINATED BIPHENYLS IN A NON-TOTALLY ENCLOSED MANNER IN HYDRAULIC SYSTEMS, HEAT TRANSFER SYSTEMS, IN MICROSCOPY AS MOUNTING MEDIUM, AND IN SMALL QUANTITIES FOR RESEARCH AND DEVELOPMENT UNTIL JULY 1, 1984 (EPA IS PROPOSING TO AMEND THE RULE GOVERNING USE OF PCBS AS MOUNTING MEDIUM AND IN RESEARCH AND DEVELOPMENT). Used in electrical capacitors, electrical transformers, vacuum pumps, and gas-transmission turbines. Formerly used in the U.S. as hydraulic fluids, plasticizers, adhesives, fire retardants, wax extenders, dedusting agents, pesticide extenders, inks, lubricants, cutting oils, in heat transfer systems, carbonless reproducing paper. PCBS /SRP: AS AROCLORS/ ARE WIDELY USED AS ENZYME INDUCERS IN RESEARCH LABORATORIES THROUGHOUT THE WORLD. THERE ARE INDICATIONS THAT CHLORINE CONTENT OF PCB MIXTURES IS RELATED TO LEVEL OF INCR ENZYMATIC ACTIVITY: MIXTURES CONTAINING LOWER PERCENTAGE OF CHLORINES WERE LESS ACTIVE THAN THOSE CONTAINING A HIGHER PERCENTAGE. /PCBs were/ used as heat-transfer fluids, organic diluents, lubricant inks, plasticizers, fire retardants, paint additives, sealing liquids, immersion oils, adhesives, dedusting agents, waxes, and as dielectric fluids for capacitors and transformers. Former uses of PCB's /as of 1974/ hydraulic fluids, plasticizer in synthetic resins, adhesives, plasticizer in rubbers, heat transfer systems, wax extenders, dedusting agents, pesticide extenders, inks, lubicants, cutting oils, carbonless reproducing paper.
Manufacturers: Monsanto, the sole domestic manufacturer of PCB's /manufactured/ this chemical in its Sauget, IL plant.
Methods of Manufacturing: ... FROM DIPHENYL & NAPHTHALENE WHICH MAY BE REACTED TO VARYING DEGREES WITH CHLORINE TO PRODUCE A NUMBER OF CMPD DESIGNATED BY VARIOUS TRADE NAMES SUCH AS AROCLOR. ... PCBS /WERE/ PREPD INDUSTRIALLY BY THE CHLORINATION OF BIPHENYL WITH ANHYDROUS CHLORINE IN THE PRESENCE OF A CATALYST SUCH AS IRON FILINGS OR FERRIC CHLORIDE. THE PRODUCTS ARE COMPLEX MIXT OF CHLOROBIPHENYLS, WHOSE DEGREE OF CHLORINATION DEPENDS PRINCIPALLY ON THE TIME OF CONTACT (12-36 HR) OF THE BIPHENYL WITH ANHYDROUS CHLORINE.
General Manufacturing Information: Commercial production /of PCB's/ was initiated in the United States in 1929 in response to the electrical industry's need for an improved dielectric insulating fluid (nonconductor of direct current) for use in transformers and capacitors which would also provide increased fire resistant benefits. Domestic /USA/ production of polychlorinated biphenyls was stopped in October 1977. All Aroclor products are characterized by a four digit number. The first two digits represent the type of molecule; 12= chlorinated biphenyl, 54= chlorinated terphenyl. Aroclor 25-- and 44-- are blends of PCB and chlorinated terphenyls (75% and 60% PCB, respectively). The last two digits give the weight percent of chlorine, Aroclor 1016 contains 41% chlorine per weight but the penta-, hexa-, heptachlorobiphenyl content is significantly reduced. ...After the initial detection of PCBs in the environment in the late 1960s, several studies confirmed their widespread occurrence throughout the global ecosystem. These studies led to the initial ban on all open uses of PCBs in the early 1970s and a later ban on their closed uses as dielectric fluids in transformers and capacitors. New transformers and capacitors, as well as PCB-containing electrical equipment, are now filled with alternative fluids.
Formulations/Preparations: Aroclor mixtures which General Electric used in transformers have contained anywhere from 13% to 60% trichlorobenzene, with the remainder being pentachlorobiphenyl or hexachlorobiphenyl or mixtures of either tri-, penta-, or hexachlorobiphenyl and tetrachlorobenzene. In the USA, Aroclor is the most familiar requested trademark, but PCBs have also been marketed as Chloretol, Dyknol, Inerteem, Noflamol, and Pyranol. In other countries, PCB formulations have been sold as Pyralene (France), Phenoclor (France), Kanechlor (Japan), Santotherm (Japan), Fenclor (Italy), Apirolio (Italy), Soval (USSR), Delor (Czechoslovakia) and Clophen (West Germany). There are 209 isomers/congeners of which 5 to 10 generally contribute more than 10% to the polychlorinated biphenyl content of Aroclor, Clophen, Phenochlor, and Kanechlor.
Impurities: A number of trace contaminants have also been identified in PCBs including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and chlorinated naphthalenes. These contaminants were first identified in certain PCB mixtures in 1970. Tri- to heptachlorodibenzofurans were found /in Aroclor/ and the total PCDF concentrations were 2-9 ppm. PCDF content: Aroclor T-1248: 0.1 ppm Tetra-, 0.4 ppm Penta-, 0.5 ppm Hexa-; Aroclor T-1254: 0.1 ppm Tetra-, 0.2 ppm Penta-, 1.4 ppm Hexa-; Aroclor T-1254: 0.2 ppm Tetra-, 0.4 ppm Penta-, 0.9 ppm Hexa-; Aroclor T-1260: 0.2 ppm Tetra-, 0.3 ppm Penta-, 0.3 ppm Hexa-; Phenoclor DP-6: 0.7 ppm Tetra-, 10.0 ppm Penta-, 2.9 ppm Hexa-; Clophen A-60: 1.4 ppm Tetra-, 5.0 ppm Penta-, 2.2 ppm Hexa-. PCDF content: Phenoclor DP-6: 0.2 ppm Tri-, 2.1 ppm Tetra-, 2.6 ppm Penta-, 5.6 ppm Hexa-; Aroclor T-1241: 2.4 ppm Tetra-, 2.7 ppm Penta-, 0.8 ppm Hexa-; Aroclor T-1242: 2.3 ppm Tetra-, 2.3 ppm Penta-; Aroclor T-1248: 0.5 ppm Tetra-, 2.3 ppm Penta-; Aroclor T-1248(c): 0.3 ppm Tri-, 5.8 ppm Tetra-, 5.6 ppm Penta-, 0.7 ppm Hexa-; Aroclor T-1254: 0.1 ppm Tetra-, 3.6 ppm Penta-, 1.9 ppm Hexa-; Aroclor T-1260: 0.8 ppm Tetra-, 0.9 ppm Penta-, 0.5 ppm Hexa-; Aroclor T-1264: 4.8 ppm Tetra-, 9.4 ppm Penta-, 2.0 ppm Hexa-; Clophen A-30: 1.6 ppm Tri-, 2.3 ppm Tetra-, 1.0 ppm Penta-; Clophen A-40: 1.5 ppm Tri-, 5.4 ppm Tetra-, 6.9 ppm Penta-; Clophen A-50: 0.7 ppm Tri-, 8.3 ppm Tetra-, 4.1 ppm Penta-, 1.8 ppm Hexa-.
Consumption Patterns: Capacitors, 70%; Transformers, 30% (1975) /Aroclors/ Considerable variation can be found in the estimates of total global production, with amounts varying from 6.1 to 12.0X10+11 g (1.3-2.5 billion pounds). The lower figure includes limited production estimates into the 1970s, while the higher figure extends to 1980 and includes former USSR production of Soval on into the 1990s.
U. S. Production: (1977) 35,555,500 lb (1970) 86 million lb (1974) 41 million lb Over 600 million kg of commercial PCBs were produced in the United States and the estimated worldwide production is approximately double this quantity.
U. S. Imports: Imports /of PCB's/ were terminated in 1980 in response to compliance with the Toxic Substances Control Act (TSCA)
U. S. Exports: (1986) ND
Laboratory Methods:
Clinical Laboratory Methods: ANALYTE: POLYCHLORINATED BIPHENYLS; MATRIX: BLOOD SERUM; RANGE: 30-10,000 NG/ML; PROCEDURE: GLC WITH ELECTRON CAPTURE DETECTOR. Urine samples containing polychlorinated biphenyls were analyzed for urinary porphyrins by a method described by Hill, for creatinine by the Jaffe procedure, nitrogen metabolites and renal function as described by Tietz, and by an enzyme immunoassay described by Fielding. The methods used are simple to do in the field, measure biologically plausible outcome, and appear to be reasonably specific and sensitive. Polychlorinated biphenyls (PCBs) were determined in blood samples from 120 women hospitalized for miscarriages and from 120 full-term pregnancy controls at the University of Aquila and University of Rome, Italy, during 1983-1984. Petroleum ether and methanol extracts of blood samples were combined in groups of 10, and each pool of 10 extracts was analyzed by silica gel column chromatography and gas chromatography with electron capture detector. The average PCB blood levels (reported as Fenclor 54, tetra and penta isomers) were 8.65 ppb in the miscarriage cases and 6.89 ppb in the controls. The average decachlorobiphenyl blood levels were 14.81 ppb for miscarriage cases and 14.90 ppb for controls. PCBs were then perchlorinated with antimony trichloride to decachlorobiphenyl and this compound also determined. Milk and fish intake in the diets of the subjects correlated negatively with the blood levels of PCBs.
Analytic Laboratory Methods: A GC METHOD IS DESCRIBED FOR ANALYSIS OF POLYCHLORINATED BIPHENYLS. ANALYSIS OF SMALL SAMPLES OF FISH EGGS, RAT BRAIN SECTIONS, AND AQUATIC MACROINVERTEBRATES FOR 78 PCB CONGENERS BY USE OF A GC WITH ELECTRON CAPTURE DETECTOR IS DESCRIBED. /POLYCHLORINATED BIPHENYLS/ HPLC ON REVERSED PHASE MICROPARTICLE COLUMN WAS USED TO RESOLVE COMMERCIAL MIXTURES OF POLYCHLORINATED BIPHENYLS, AROCLOR 1221, 1016 & 1254. Chlorinated anilines are coupled with chlorinated benzenes by using an excess of the latter reactant which also serves as the solvent medium. The coupling reaction proceeds smoothly after the addition of isoamyl nitrate, and the PCB product is readily isolated after a series of chromatographic procedures. ANALYTE: POLYCHLORINATED BIPHENYL (PCB); MATRIX: AIR; RANGE: 0.01-10 MG/CU M; PROCEDURE: GC. Analyte: polychlorobiphenyls; range: 0.4-4 ug/sample; procedure: gas chromatography with electron capture detector; matrix: not given; precision: 0.044. NIOSH Method 8004. Determination of polychlorobiphenyls in serum by gas chromatography with electron capture detection. A method for the separation of PCBs from certain organochlorine pesticides requires elution of the PCBs with petroleum ether. Determination of PCB content in the sample is done by electron capture GLC or by halogen specific microcoulometric or electrolytic GLC. A method for the semi-quantitative estimation of PCB in adipose tissue consists of extraction with petroleum ether and acetonitrile partitioning. The PCBs are then determined by thin layer chromatography. A macro method for the determination of PCBs in human milk consists of extraction from the fat with acetone and hexane. Identification and quantification are done with GLC using an electron capture detector. The GLC sensitivity limit for PCBs is 20 ppb theoretical and 50 ppb practical based on the whole milk sample weight. A micro method for the determination of PCBs in human milk consists of extraction with acetonitrile. The column eluate containing PCBs is concentrated and analyzed by GLC with an electron capture detector. PCBs with the highest vapor pressures (fewest chlorines) in Aroclors 1016, 1242, 1254, and 1268 were enriched in the vapor phase relative to the original Aroclor during the volatilization from a glass surface for up to 8 hr. Thus, visual matching of chromatograms with those of Aroclor standards may not be sufficient to identify a specific Aroclor. The alternating current plasma detector for gas chromatography is shown to be a useful detector for selective organochlorine detection. The detector incorporates a simple design and a power source that produces a stable discharge which does not extinguish under high solvent concn conditions. The plasma discharge produces diatomic emission of C-Cl species, with few atomic chlorine emission lines. Detection limits for various organochlorine compounds are approximately 1.0 ng/sec. The detector exhibits a complex response dependent on molecular structure and environment. A 10 ml aliquot of number 2 fuel oil was spiked with 10 mg of Aroclor 1254 (PCB) and the parallel flame ionization detector chromatogram of PCB in fuel oil was run under the same conditions as the alternating current plasma detector chromatogram. Alternating current plasma detection greatly simplified the complex chromatogram of fuel oil and PCB, in addition to providing valuable qualitative information. A two-dimensional capillary gas chromatographic system was used for isomer specific detn of polychlorinated biphenyls. Two gas capillary gas chromatographs were interfaced with each other and other components of the system through a 12 port, 2 position valve. The gas chromatographs could also be operated independently, in a dual column (heart cutting) mode. Unresolved components were transferred to the second column by switching the valve position. With the use of on-column injection and low volume transfer lines, very efficient separation of PCBs was obtained (better than 85% resolution). Ambiguities in the confirmation of congeners in environmental samples are overcome by use of the system in the dual column reaction mode. Here analytes of interest are made to pass through an in line reactor, the products and residual analytes are cryogenically trapped and introduced by flash heating onto the second column. Products are formed by loss of chlorine substituents from the phenyl rings. Analysis was made of serum from an occupationally exposed and a non occupationally exposed individual. From chromatographic profiles, the concn of congener 180 in the non-exposed serum sample was determined to be 0.5 ppb. A simple, rapid, low cost and uniform single-step clean-up procedure with a column containing 2 silica gel packings of different mesh size was developed for the quantitative detn of polychlorinated biphenyls (PCBs) by capillary gas chromatography. 9 complex liquid and solid samples were put through the clean-up procedure: (1) fish (freshwater bream from the river Elbe, canned tunny), (2) rolled oats, (3) river sediment, (4) lime from the scrubber of an industrial waste incinerator, (5) fly ash from the heat exchanger of an industrial waste incinerator, (6) olive oil, (7) waste motor oil, (8) transformer oil, and (9) oil from a tempering bath. Only the transformer oil (17,017 ppm PCBs), oil from the tempering bath (21.7 ppm), and waste motor oil (11.5 ppm) were heavily contaminated with PCBs. The concn of PCBs in freshwater bream and river sediment were 0.145 and 0.069 ppm, respectively. PCBs could not be detected in the canned tunny, lime and fly ash from the waste incinerator, rolled oats and olive oil. Gas chromatograms taken after clean-up demonstrated nearly all accompanying substances were separated by the procedure. A reproducibility of + or - 4.7% was determined using four 20 ul motor oil samples contaminated with PCBs. The recovery rate of PCBs from waste oil spiked with 20 pg PCB/ul column eluant was 92.7%. OSW Method 3545. Accelerated solvent extraction applicable to extracting water insoluble or slightly soluble semivolatile organic compounds from soils, clays, sediments, sludges, and solid wastes. Compounds such as organochlorine and organophosphorus pesticides, PCBs, chlorinated herbicides, and semivolatile organics are extracted depending on the mix of solvents used. OSW Method 9078. Screening method for Polychlorinated Biphenyls (PCBs) in Soil applicable to determining the amount of PCB contamination in soils, sand, gravel, loam, clay, and sediments. The range of the method is 2-2000 ug/g. This test is not specific for individual Aroclors. AOAC Method 974.21. Polychlorinated Biphenyls in Paper and Paperboard by Gas Chromatographic Method.
Sampling Procedures: Filter + solid sorbent (13 mm fiber + Florisil, 100 mg/50 mg). At examination spot urine specimens, voided directly into opaque containers were collected. Specimens were preserved within 2 hr of collection with ethylene diamine tetra-acetic acid disodium calcium salt and sodium carbonate and frozen. They were shipped on dry ice to their destination for analysis and then frozen until analysis.
Special References:
Special Reports: ALVARES AP ET AL; NATL RES COUNC CAN, (REP) NRCC/CNRC 18978, WORKSHOP COMB EFF XENOBIOTICS, 127-49 (1982). REVIEW ON ENZYME INDUCTIVE PROPERTIES OF PCBS. TSCA CHIPs present a preliminary assessment of polychlorinated biphenyl's potential for injury to human health & the environment (available at EPA's TSCA Assistance Office: (202) 554-1404 USEPA; Environmental Assessment of PCBs in the Atmosphere (1976) MTR-7210. USEPA; Ambient Water Quality Criteria Doc: Polychlorinated Biphenyls (1980) EPA 440/5-80-068. USEPA; Health Assessment Document for Polychlorinated Biphenyls (Draft) (1985). US Dept of Interior/Fish & Wildlife Service Contaminant Reviews; Polychlorinated Biphenyls Hazards to Fish, Wildlife, and Invertebrates: A Synoptic Review Biol Rept No (85) 1.7 (1986). WHO; Environ Health Criteria: Polychlorinated Biphenyls and Terphenyls (1976). Nat'l Research Council Canada; Polychlorinated Biphenyls: Biological Criteria for an Assessment of their Effects on Environmental Quality (1978) NRCC No. 16077. Nat'l Research Council Canada; A Case Study of a Spill of Industrial Chemicals- Polychlorinated Biphenyls and Chlorinated Benzenes (1980) NRCC No. 17586. NAS/National Research Council; Polychlorinated Biphenyls (1979). Ming Lin J, Que Hee S; Am Ind Hyg Assoc J 48 (7): 599-607 (1987). A comparison of various analytical methods for Arcolor is presented. DHHS/ATSDR; Toxicological Profile for Selected PCBs (Arochlor-1260, 1254, -1248, -1242, -1232, -1221, and -1016) (Update ) TP-92/16 (1993) USEPA; Drinking Water Quality Criteria Document: Polychlorinated Biphenyls (PCBs) ECAO-CIN-414 (1987) U.S. Department of Health & Human Services/National Toxicology Program; Tenth Report on Carcinogens. National Institutes of Environmental Health Sciences. The Report on Carcinogens is an informational scientific and public health document that identifies and discusses substances (including agents, mixtures, or exposure circumstances) that may pose a carcinogenic hazard to human health. Polychlorinated biphenyls (1336-36-3) was first listed in the Second Annual Report on Carcinogens (1981) as reasonably anticipated to be a human carcinogen.
Synonyms and Identifiers:
Related HSDB Records: 6352 [AROCLOR 1016] (Mixture Component) 6353 [AROCLOR 1221] (Mixture Component) 6354 [AROCLOR 1232] (Mixture Component) 6355 [AROCLOR 1242] (Mixture Component) 6356 [AROCLOR 1248] (Mixture Component) 6357 [AROCLOR 1254] (Mixture Component) 1822 [AROCLOR 1260] (Mixture Component) 946 [2,4,5,2',4',5'-HEXACHLOROBIPHENYL] (Mixture Component) 3947 [2,4,5,3',4',5'-HEXACHLOROBIPHENYL] (Mixture Component) 3948 [3,4,5,3',4',5'-HEXACHLOROBIPHENYL] (Mixture Component) 3949 [3,4,3',4'-TETRACHLOROBIPHENYL] (Mixture Component)
Synonyms: Aroclor 1,1'-Biphenyl, chloro derivs Biphenyl, polychloro- Caswell no 672A Chlorextol Chlorinated biphenyl Chlorinated diphenyl Chlorinated diphenylene Chloro biphenyl Chloro 1,1-biphenyl- Clophen Dykanol EPA pesticide chemical code 017801 Fenclor Inerteen Kanechlor Montar Monter Noflamol PCB Phenoclor Polychlorobiphenyl Pyralene Pyranol Santotherm Santotherm fr Sovol Therminol Therminol fr-1
Associated Chemicals: Aroclor;12767-79-2 Formulations/Preparations: Aroclor mixtures which General Electric used in transformers have contained anywhere from 13% to 60% trichlorobenzene, with the remainder being pentachlorobiphenyl or hexachlorobiphenyl or mixtures of either tri-, penta-, or hexachlorobiphenyl and tetrachlorobenzene. In the USA, Aroclor is the most familiar requested trademark, but PCBs have also been marketed as Chloretol, Dyknol, Inerteem, Noflamol, and Pyranol. In other countries, PCB formulations have been sold as Pyralene (France), Phenoclor (France), Kanechlor (Japan), Santotherm (Japan), Fenclor (Italy), Apirolio (Italy), Soval (USSR), Delor (Czechoslovakia) and Clophen (West Germany). There are 209 isomers/congeners of which 5 to 10 generally contribute more than 10% to the polychlorinated biphenyl content of Aroclor, Clophen, Phenochlor, and Kanechlor.
Shipping Name/ Number DOT/UN/NA/IMO: UN 2315; Polychlorinated biphenyls, liquid or solid IMO 9.0; Polychlorinated biphenyls, liquid or solid
Standard Transportation Number: Return to Home Air Purifier Index from PCB Learn about the hazards of other Household Chemical Products Top of Page |
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